IR 感谢列基金会的博士奖学金奖。

<ol>
	<li>Koski, K. J., Akhenblit, P., McKiernan, K., Yarger, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-invasive+determination+of+the+complete+elastic+moduli+of+spider+silks.">Non-invasive determination of the complete elastic moduli of spider silks.</a> Nat. Mater. 12 (3), 262-267 (2013).</li><li>Palombo, F., Madami, M., Stone, N., Fioretto, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+mapping+with+chemical+specificity+by+confocal+Brillouin+and+Raman+microscopy.">Mechanical mapping with chemical specificity by confocal Brillouin and Raman microscopy.</a> Analyst. 139 (4), 729-733 (2014).</li><li>Scarcelli, G., Yun, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+Brillouin+optical+microscopy+of+the+human+eye.">In vivo Brillouin optical microscopy of the human eye.</a> Opt. Exp. 20 (8), 9197-9202 (2012).</li><li>Scarcelli, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noncontact+three-dimensional+mapping+of+intracellular+hydromechanical+properties+by+Brillouin+microscopy.">Noncontact three-dimensional mapping of intracellular hydromechanical properties by Brillouin microscopy.</a> Nat. Methods. 12 (12), 1132-1134 (2015).</li><li>Traverso, A. J., Thompson, J. V., Steelman, Z. A., Meng, Z., Scully, M. O., Yakovlev, V. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual+Raman-Brillouin+microscope+for+chemical+and+mechanical+characterization+and+imaging.">Dual Raman-Brillouin microscope for chemical and mechanical characterization and imaging.</a> Anal. Chem. 87 (15), 7519-7523 (2015).</li><li>Antonacci, G., Foreman, M. R., Paterson, C., T&#246;r&#246;k, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spectral+broadening+in+Brillouin+imaging.">Spectral broadening in Brillouin imaging.</a> Appl. Phys. Lett. 103 (22), 221105 (2013).</li><li>Antonacci, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+plaque+stiffness+by+Brillouin+microscopy+in+experimental+thin+cap+fibroatheroma.">Quantification of plaque stiffness by Brillouin microscopy in experimental thin cap fibroatheroma.</a> J. R. Soc. Interface. 12 (112), 20150483 (2015).</li><li>Grubbs, W. T., MacPhail, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+resolution+stimulated+Brillouin+gain+spectrometer.">High resolution stimulated Brillouin gain spectrometer.</a> Rev. Sci. Instrum. 65 (1), 34-41 (1994).</li><li>Ballmann, C. W., Thompson, J. V., Traverso, A. J., Meng, Z., Scully, M. O., Yakovlev, V. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stimulated+Brillouin+scattering+microscopic+imaging.">Stimulated Brillouin scattering microscopic imaging.</a> Sci Rep. 5, 18139 (2015).</li><li>Remer, I., Bilenca, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Background-free+Brillouin+spectroscopy+in+scattering+media+at+780+nm+via+stimulated+Brillouin+scattering.">Background-free Brillouin spectroscopy in scattering media at 780 nm via stimulated Brillouin scattering.</a> Opt. Lett. 41 (5), 926-929 (2016).</li><li>Remer, I., Bilenca, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-speed+stimulated+Brillouin+scattering+spectroscopy+at+780+nm.">High-speed stimulated Brillouin scattering spectroscopy at 780 nm.</a> APL Photonics. 1 (6), 061301 (2016).</li><li>She, C. Y., Moosm&#252;ller, H., Herring, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coherent+light+scattering+spectroscopy+for+supersonic+flow+measurements.">Coherent light scattering spectroscopy for supersonic flow measurements.</a> Appl. Phys. B-Lasers O. 46 (4), 283-297 (1988).</li><li>Fiore, A., Zhang, j., Peng Shao, ., Yun, S. H., Scarcelli, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-extinction+virtually+imaged+phased+array-based+Brillouin+spectroscopy+of+turbid+biological+media.">High-extinction virtually imaged phased array-based Brillouin spectroscopy of turbid biological media.</a> Appl. Phys. Lett. 108 (20), 203701 (2016).</li></ol>

作者没有什么可透露的。

该系统在图 1中所示, 设计为在 18 "x 24" 板上构建, 可以垂直安装在光学表上, 从而便于放置水样样品。因此, 重要的是要强烈收紧所有的光学和机械元件, 并确保泵和探头梁是共线和同心的各种元素之前, 照亮样品在离轴几何。
观察受激布里渊增益信号的困难可能是由于过多的杂散泵反射, 掩盖了水样样品的弱布里渊增益 (~ 10-6)。为了解决这些可能遇到的困?...

自发布里渊光谱学近年来已经建立, 作为一种有价值的方法, 用于机械分析软材料, 如液体, 真实组织, 组织幻影和生物细胞1,2, 3,4,5,6,7。在这种方法中, 一个单一的激光照射的样品和光, 是弹性散射从自发的热声波在介质中收集的分光计, 提供有用的信息的粘弹性性质的样品。自发布里渊频谱包括两个布里渊峰在声波斯托克斯和反斯托克斯共振的材料, 和瑞利峰在照明激光频率 (由于弹性散射光)。对于布里渊散射几何, 布里渊频率由几个 GHz 从照明激光频率转移, 有数百兆赫的频谱宽度。
当扫描法布里-珀罗光谱仪已 systems-of-choice 获得自发布里渊光谱在软物质1,2, 最近的技术进步在几乎成像相阵列 (VIPA)光谱仪已启用显着更快 (秒) 布里渊测量与适当的频谱分辨率 (子 GHz)3,4,5,6,7。在本协议中, 我们提出了一个不同的, 高速, 高光谱分辨率, 精确的布里渊光谱仪的基础上检测 continuous-wave-受激-布里渊散射 (CW-SBS) 光从 non-turbid 和混浊样品在一个几乎反散射几何。
在 cw-SBS 光谱中, continuous-wave (cw) 泵和探针激光器, 在频率上略谐, 在样品中重叠以刺激声波。当泵与探头横梁的频率差与材料的特定声学共振相匹配时, 探头信号的放大或 deamplification 分别由受激布里渊增益或损耗 (SBG/SBL) 过程提供;否则, 没有 SBS (de) 放大发生8,9,10,11。因此, SBG (SBL) 频谱可以通过扫描在材料布里渊共振的激光之间的频率差和检测增加 (减少), 或增益 (损失), 在探针强度由于 SBS。与自发布里渊散射不同的是, 弹性散射背景在 SBS 中是固有的, 在混浊和 non-turbid 样品中都能得到优异的布里渊对比度, 而不需要 VIPA 的瑞利滤波器。光谱仪10,11,13。
CW-SBS 光谱仪的主要组成部分是泵浦和探针激光器以及受激布里渊增益/损耗检测器。对于高光谱分辨率, 高速 CW-SBS 光谱学, 激光器需要单 (#60; 10 MHz 线宽) 与足够宽波长调谐 (20-30 ghz) 和扫描率 (和 #62; 200 GHz/秒), 长期频率稳定 (和 #60; 50MHz/小时) 和低强度噪音。此外, 该泵 (探头) 横梁上需要具有几百 (数十) 兆瓦的功率的线性偏振和衍射有限激光束。最后, 应设计受激布里渊增益/损耗检测器, 以可靠地检测弱向后受激布里渊增益/损耗 (SBG/SBL) (10-5 -10-6) 的软物质。为了满足这些需求, 我们选择了分布式反馈 (DFB) 二极管激光器耦合到极化维护光纤和受激布里渊增益/损耗探测器结合 ultra-narrowband 原子蒸气缺口滤波器single-modulation 锁相放大器, 如图 1所示。此检测方案使 SBG 信号的强度加倍, 同时显著降低探头强度中的噪声, 而所需的 SBG 信号嵌入11。请注意, 在我们的 SBS 光谱仪中使用的原子气陷式过滤器的作用是显著减少不需要的杂散泵反射的检测, 而不是减少在 VIPA 光谱仪中检测到的弹性散射背景自发瑞利和布里渊散射光。使用下面详述的协议, 可以构造一个 CW-SBS 光谱仪, 能够获得水和组织幽灵的透射谱, 其 SBG 水平低至 10-6 , #60; 35 MHz 布里渊移位测量精度和在100毫秒以内。
<img alt="Figure 1" src="/files/ftp_upload/55527/55527fig1.jpg"> 
图 1: 连续波受激布里渊散射 (CW-SBS) 光谱仪.两个 continuous-wave 泵和探针二极管激光器 (DL), 频率谐周围的布里渊转移的样本, 是耦合成极化维护单模光纤与直 c1和 c2, 分别。测量泵探头的频率差, 通过检测从泵剥离的光束和使用一组光纤分配器 (FS)、快速光电探测器 (平板显示器) 和频率计数器 (FC) 的探测激光器之间的跳动频率。S 极化探头光束 (浅红色), 扩展使用 Keplerian 光束膨胀器 (l1和 l2), 是右圆极化的四分之一波板 (λ1/4), 并专注于样本 (S) 由一个消色差透镜 (l3)。为有效的 SBS 相互作用和光隔离, 泵梁 (深红色), 扩大使用 Keplerian 扩束器 (l5和 l6), 是第一个 P 极化使用波板λ2/4), 然后通过极化传输光束分配器 (PBS), 并最终留下圆极化的四分之一波板 (λ2/4), 并专注于样品与无色透镜 (l4; 与 l3相同)。请注意, 泵和探头横梁几乎 counter-propagate 在样品中, 并使用 S 型偏振器 (p) 来防止 p 极化泵光束 (来自λ1/4) 进入探针激光器。对于锁定检测, 泵浦光束在fm 上正弦调制, 并带有声光调制器 (AOM)。SBG 信号, 表现为强度变化在频率fm (参见插页), 被解调用由大面积光电二极管 (PD) 检测后的锁定放大器。为了显著消除光电二极管中的杂散泵反射, 在泵浦波长周围使用窄带布拉格滤波器 (BF) 和原子陷波器 (85RB), 同时用遮光虹膜 (I)。数据通过连接到个人电脑 (PC) 的数据采集卡进行记录, 以进一步分析布里渊频谱。所有折叠镜 (m1-m6) 用于将光谱仪放在一个 18 "×24" 板上, 垂直安装在光学工作台上, 以方便水样样品的放置。<a href="https://ecsource-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/55527/55527fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>

<table><tbody><tr><td>Probe diode laser head and controller</td><td>Toptica Photonics</td><td>SYST DL-100-DFB</td><td>Quantity: 1</td></tr><tr><td>Pump amplified diode laser and controller</td><td>Toptica Photonics</td><td>SYST TA-pro-DFB</td><td>Quantity: 1</td></tr><tr><td>FC/APC fiber dock</td><td>Toptica Photonics</td><td>FiberDock&amp;nbsp;</td><td>Quantity: 3</td></tr><tr><td>High power single mode polarization maintaining FC/APC fiber patchcord</td><td>Toptica Photonics</td><td>OE-000796</td><td>Quantity: 1</td></tr><tr><td>FC/APC fiber collimation with adjustable collimation optics</td><td>Toptica Photonics</td><td>FiberOut</td><td>Quantity: 1</td></tr><tr><td>FC/APC fiber fixed collimator</td><td>OZ Optics</td><td>HPUCO-33A-780-P-6.1-AS</td><td>Quantity: 1</td></tr><tr><td>Single mode polarization maintaining fiber splitter 33:67</td><td>OZ Optics</td><td>FOBS-12P-111-4/125-PPP-780-67/33-40-3A3A3A-3-1</td><td>Quantity: 1</td></tr><tr><td>Single mode polarization maintaining fiber splitter 50:50</td><td>OZ Optics</td><td>FOBS-12P-111-4/125-PPP-780-50/50-40-3S3A3A-3-1</td><td>Quantity: 1</td></tr><tr><td>f=25 mm, &amp;Oslash;1/2&quot; Achromatic Doublet, SM05-Threaded Mount, ARC: 650-1050 nm</td><td>Thorlabs</td><td>AC127-025-B-ML</td><td>Quantity: 1</td></tr><tr><td>f=30 mm, &amp;Oslash;1&quot; Achromatic Doublet, SM1-Threaded Mount, ARC: 650-1050 nm</td><td>Thorlabs</td><td>AC254-30-B-ML</td><td>Quantity: 2</td></tr><tr><td>f=50 mm, &amp;Oslash;1&quot; Achromatic Doublet, SM1-Threaded Mount, ARC: 650-1050 nm</td><td>Thorlabs</td><td>AC254-50-B-ML</td><td>Quantity: 1</td></tr><tr><td>f=100 mm, &amp;Oslash;1&quot; Achromatic Doublet, SM1-Threaded Mount, ARC: 650-1050 nm</td><td>Thorlabs</td><td> AC254-100-B-ML</td><td>Quantity: 1</td></tr><tr><td>f=200 mm, &amp;Oslash;1&quot; Achromatic Doublet, SM1-Threaded Mount, ARC: 650-1050 nm</td><td>Thorlabs</td><td> AC254-200-B-ML</td><td>Quantity: 1</td></tr><tr><td>&amp;Oslash;1/2&quot; Broadband Dielectric Mirror, 750-1100 nm</td><td>Thorlabs</td><td> BB05-E03</td><td>Quantity: 4</td></tr><tr><td>&amp;Oslash;1&quot; Broadband Dielectric Mirror, 750-1100 nm</td><td>Thorlabs</td><td> BB1-E03</td><td>Quantity: 2</td></tr><tr><td>1&quot; Polarizing beamsplitter cube, 780 nm</td><td>Thorlabs</td><td> PBS25-780</td><td>Quantity: 1</td></tr><tr><td>&amp;Oslash;1&quot; Linear polarizer with N-BK7 protective windows, 600-1100 nm</td><td>Thorlabs</td><td> LPNIRE100-B</td><td>Quantity: 1</td></tr><tr><td>Shearing Interferometer with a 1-3 mm Beam Diameter Shear Plate</td><td>Thorlabs</td><td>SI035</td><td>Quantity: 1</td></tr><tr><td>6-Axis Locking kinematic optic mount</td><td>Thorlabs</td><td> K6XS</td><td>Quantity: 4</td></tr><tr><td>Compact five-axis platform</td><td>Thorlabs</td><td> PY005</td><td>Quantity: 1</td></tr><tr><td>Pedestal mounting adapter for 5-axis platform</td><td>Thorlabs</td><td> PY005A2</td><td>Quantity: 1</td></tr><tr><td>Polaris low drift &amp;Oslash;1/2&quot; kinematic mirror mount, 3 adjusters</td><td>Thorlabs</td><td> POLARIS-K05</td><td>Quantity: 4</td></tr><tr><td>Lens mount for &amp;Oslash;1&quot; optics</td><td>Thorlabs</td><td> LMR1</td><td>Quantity: 5</td></tr><tr><td>Adapter with external SM1 threads and Internal SM05 threads, 0.40&quot; thick</td><td>Thorlabs</td><td> SM1A6T</td><td>Quantity: 1</td></tr><tr><td>Rotation mount for &amp;Oslash;1&quot; optics</td><td>Thorlabs</td><td> RSP1</td><td>Quantity: 2</td></tr><tr><td>1&quot; Kinematic prism mount</td><td>Thorlabs</td><td> KM100PM</td><td>Quantity: 1</td></tr><tr><td>Graduated ring-activated SM1 iris diaphragm</td><td>Thorlabs</td><td> SM1D12C</td><td>Quantity: 1</td></tr><tr><td>Post-mounted iris diaphragm, &amp;Oslash;12.0 mm max aperture</td><td>Thorlabs</td><td>ID12</td><td>Quantity: 2</td></tr><tr><td>1/2&quot; translation stage with standard micrometer</td><td>Thorlabs</td><td>MT1</td><td>Quantity: 3</td></tr><tr><td>&amp;Oslash;1&quot; Pedestal pillar post, 8-32 taps, L = 1&quot;</td><td>Thorlabs</td><td>RS1P8E</td><td>Quantity: 1</td></tr><tr><td>&amp;Oslash;1&quot; Pedestal pillar post, 8-32 taps, L = 1.5&quot;</td><td>Thorlabs</td><td>RS1.5P8E</td><td>Quantity: 2</td></tr><tr><td>&amp;Oslash;1&quot; Pedestal pillar post, 8-32 taps, L = 2&quot;</td><td>Thorlabs</td><td>RS2P8E</td><td>Quantity: 4</td></tr><tr><td>&amp;Oslash;1&quot; Pedestal pillar post, 8-32 taps, L = 2.5&quot;</td><td>Thorlabs</td><td>RS2.5P8E</td><td>Quantity: 1</td></tr><tr><td>&amp;Oslash;1&quot; Pedestal pillar post, 8-32 taps, L = 3&quot;</td><td>Thorlabs</td><td>RS3P8E</td><td>Quantity: 4</td></tr><tr><td>Short clamping fork</td><td>Thorlabs</td><td>CF125</td><td>Quantity: 12</td></tr><tr><td>Mounting base</td><td>Thorlabs</td><td>BA1S</td><td>Quantity: 8</td></tr><tr><td>Large V-Clamp with PM4 Clamping Arm, 2.5&quot; Long, Imperial</td><td>Thorlabs</td><td>VC3C</td><td>Quantity: 1</td></tr><tr><td>&amp;Oslash;1/2&quot; Post holder, spring-loaded hex-locking thumbscrew, L = 1&quot;</td><td>Thorlabs</td><td>PH1</td><td>Quantity: 2</td></tr><tr><td>&amp;Oslash;1/2&quot; Post holder, spring-loaded hex-locking thumbscrew, L = 1.5&quot;</td><td>Thorlabs</td><td>PH1.5</td><td>Quantity: 2</td></tr><tr><td>&amp;Oslash;1/2&quot; Post holder, spring-loaded hex-locking thumbscrew, L = 2&quot;</td><td>Thorlabs</td><td>PH2</td><td>Quantity: 6</td></tr><tr><td>&amp;Oslash;1/2&quot; Optical post, SS, 8-32 setscrew, 1/4&quot;-20 tap, L = 1&quot;</td><td>Thorlabs</td><td>TR1</td><td>Quantity: 2</td></tr><tr><td>&amp;Oslash;1/2&quot; Optical post, SS, 8-32 setscrew, 1/4&quot;-20 tap, L = 1.5&quot;</td><td>Thorlabs</td><td>TR1.5</td><td>Quantity: 2</td></tr><tr><td>&amp;Oslash;1/2&quot; Optical post, SS, 8-32 setscrew, 1/4&quot;-20 tap, L = 2&quot;</td><td>Thorlabs</td><td>TR2</td><td>Quantity: 6</td></tr><tr><td>Aluminum breadboard 18&quot; x 24&quot; x 1/2&quot;, 1/4&quot;-20 taps</td><td>Thorlabs</td><td>MB1824</td><td>Quantity: 1</td></tr><tr><td>12&quot; Vertical bracket for breadboards, 1/4&quot;-20 holes, 1 piece</td><td>Thorlabs</td><td>VB01</td><td>Quantity: 2</td></tr><tr><td>Si photodiode, 40 ns Rise time, 400 - 1100 nm, 10 mm x 10 mm active area</td><td>Thorlabs</td><td> FDS1010</td><td>Quantity: 1</td></tr><tr><td>Waveplate, zero order, 1/4 wave 780nm</td><td>Tower Optics</td><td>Z-17.5-A-.250-B-780</td><td>Quantity: 2</td></tr><tr><td>Waveplate, zero order, 1/2 wave 780nm</td><td>Tower Optics</td><td>Z-17.5-A-.500-B-780</td><td>Quantity: 1</td></tr><tr><td>Fiber coupled ultra high speed photodetector</td><td>Newport</td><td>1434</td><td>Quantity: 1</td></tr><tr><td>Gimbal optical miror mount</td><td>Newport</td><td>U100-G2H ULTIMA</td><td>Quantity: 3</td></tr><tr><td>linear stage with 25 mm travel range</td><td>Newport</td><td>&amp;nbsp;M-423&amp;nbsp;</td><td>Quantity: 1</td></tr><tr><td>Lockable differential micrometer, 25 mm coarse, 0.2 mm fine,11 lb. load</td><td>Newport</td><td>&amp;nbsp;DM-25L</td><td>Quantity: 1</td></tr><tr><td>XYZ Motor linear stage</td><td>Applied Scientific Instrumentation</td><td>LS-50</td><td>Quantity: 3</td></tr><tr><td>Stage controller</td><td>Applied Scientific Instrumentation</td><td>MS-2000</td><td>Quantity: 1</td></tr><tr><td>Sample holder</td><td>Home made</td><td>Custom</td><td>Quantity: 1</td></tr><tr><td>Rubidium 85 Fused Silica spectroscopy cell with flat AR-coated windows, 150 mm length, 25mm diameter</td><td>Photonics Technologies</td><td>SC-RB85-25x150-Q-AR</td><td>Quantity: 1</td></tr><tr><td>Thermally conductive pad 300 mm x 300 mm</td><td>BERGQUIST</td><td>Q3AC 300MMX300MM SHEET</td><td>Quantity: 1</td></tr><tr><td>Heat tape 0.15 mm x 2.5&amp;nbsp; mm x 5 m, 4.29&amp;nbsp; W/m</td><td>KANTHAL</td><td>8908271</td><td>Quantity: 1</td></tr><tr><td>Polytetrafluoroethylene tape 1/2&#039;&#039; x 12 m</td><td>Teflon tape</td><td>R.G.D</td><td>Quantity: 1</td></tr><tr><td>Reflecting Bragg grating bandpass filter</td><td>OptiGrate</td><td>SPC-780</td><td>Quantity: 1</td></tr><tr><td>High frequncy aousto optic modulator</td><td>Gooch and Housego</td><td>15210</td><td>Quantity: 1</td></tr><tr><td>Aousto optic modulator RF driver, frequncy: 210 MHz&amp;nbsp;</td><td>Gooch and Housego</td><td>MHP210-1ADS2-A1</td><td>Quantity: 1</td></tr><tr><td>High frequncy lock-in amplifier&amp;nbsp;</td><td>Stanford Research Systems</td><td>SR844</td><td>Quantity: 1</td></tr><tr><td>Frequency counter</td><td>Phase Matrix</td><td>EIP 578B</td><td>Quantity: 1</td></tr><tr><td>Arbitrary function Generator</td><td>Tektronix</td><td>AFG2021</td><td>Quantity: 2</td></tr><tr><td>Data acquisition (DAQ) module</td><td>National Instruments</td><td>NI USB-6212 BNC</td><td>Quantity: 1</td></tr><tr><td>Data acquisition (DAQ) software&amp;nbsp;</td><td>National Instruments</td><td>LabVIEW 2014</td><td>Quantity: 1</td></tr><tr><td>Regulated DC power supply&amp;nbsp; dual 0-30V 5A</td><td>MEILI</td><td>MCH-305D-ii</td><td>Quantity: 1</td></tr><tr><td>Thermocouple</td><td>MRC</td><td>TP-01</td><td>Quantity: 1</td></tr><tr><td>Thermometer</td><td>MRC</td><td>TM-5007</td><td>Quantity: 1</td></tr><tr><td>Coaxial low pass filter DC-1.9 MHz</td><td>Mini Circuits</td><td>BLP-1.9+</td><td>Quantity: 1</td></tr><tr><td>20% lipid-emulsion</td><td>Sigma-Aldrich</td><td>I141-100ml</td><td>Quantity: 1</td></tr><tr><td>round 25 mm diameter cover glass thick:1 #</td><td>Menzel Glaser</td><td>150285</td><td>Quantity: 1</td></tr><tr><td>Computational software&amp;nbsp;</td><td>MathWorks</td><td>MATLAB 2015a</td><td></td></tr></tbody></table>

high-speed continuous-wave stimulated brillouin scattering spectrometer for material analysis

近年来, 自发布里渊光谱仪在非接触性分析软物质, 如水溶液和生物材料等方面的使用有了显著增加, 获得了快速的采集时间。在这里, 我们讨论的组装和运行的布里渊光谱仪, 使用受激布里渊散射 (SBS) 测量的受激布里渊增益 (SBG) 光谱的水和脂 emulsion-based 组织样样品在传输模式与 &lt; 10 兆赫光谱分辨率和 &lt; 35 MHz 布里渊位移测量精度在 &lt; 100 ms. 分光计由两个近拉曼光 continuous-wave (CW) 窄线宽激光器组成, 其频率失谐的 780 nm 扫描通过材料布里渊移位。通过采用 ultra-narrowband 热 rubidium-85 气陷式过滤器和相敏探测器, 与现有的 CW-SBS 光谱仪相比, SBG 信号的信噪比得到显著提高。这种改进使测量的 SBG 频谱高达100倍的更快的采集时间, 从而促进高光谱分辨率和高精度的布里渊分析软材料的高速。

图 2b和3b显示了蒸馏水和脂质乳胶组织幻像样本的典型点 SBG 谱 (2.25 散射事件和 45 cm-1的衰减系数) 分别在 10 ms 和100毫秒内测量。为了比较, 我们测量了十年代的 SBG 谱, 如图 2a和3a所示。在这些测量中, rubidium-85 蒸气细胞被加热到90° c 衰减杂散泵反射通过 ~ 104和传输和 #62; 95% 探针光;在 h11?...

Watch this Scientific Journal Video about High-speed Continuous-wave Stimulated Brillouin Scattering Spectrometer for Material Analysis at JoVE.com

High-speed Continuous-wave Stimulated Brillouin Scattering Spectrometer for Material Analysis

我们描述了一个快速 continuous-wave-受激-布里渊散射 (CW-SBS) 光谱仪的构造。该光谱仪采用单二极管激光器和原子蒸气缺口滤波器来获得高光谱分辨率的混浊/non-turbid 样品的透射光谱, 其速度比现有的 CW-SBS 光谱仪快100倍。这种改进可以实现高速布里渊材料分析。

用于材料分析的高速连续波受激布里渊散射光谱仪

Recent years have witnessed a significant increase in the use of spontaneous Brillouin spectrometers for non-contact analysis of soft matter, such as ...

high-speed-continuous-wave-stimulated-brillouin-scattering

Universidad San Sebastian

Research

JoVE Journal

Engineering

10.1K 次观看.  Ben-Gurion University of the Negev. 我们描述了一个快速 continuous-wave-受激-布里渊散射 (CW-SBS) 光谱仪的构造。该光谱仪采用单二极管激光器和原子蒸气缺口滤波器来获得高光谱分辨率的混浊/non-turbid 样品的透射光谱, 其速度比现有的 CW-SBS 光谱仪快100倍。这种改进可以实现高速布里渊材料分析。 

视频: High-speed Continuous-wave Stimulated Brillouin Scattering Spectrometer for Material Analysis

Rejection of Fluorescence Background in Resonance and Spontaneous Raman Microspectroscopy

Raman spectroscopy is often plagued by a strong fluorescent background, particularly for biological samples. If a sample is excited with a train of ultrafast pulses, a system that can temporally separate spectrally overlapping signals on a picosecond timescale can isolate promptly arriving Raman scattered light from late-arriving fluorescence light. Here we discuss the construction and operation of a complex nonlinear optical system that uses all-optical switching in the form of a low-power optical Kerr gate to isolate Raman and fluorescence signals. A single 808 nm laser with 2.4 W of average power and 80 MHz repetition rate is split, with approximately 200 mW of 808 nm light being converted to &lt; 5 mW of 404 nm light sent to the sample to excite Raman scattering. The remaining unconverted 808 nm light is then sent to a nonlinear medium where it acts as the pump for the all-optical shutter. The shutter opens and closes in 800 fs with a peak efficiency of approximately 5%. Using this system we are able to successfully separate Raman and fluorescence signals at an 80 MHz repetition rate using pulse energies and average powers that remain biologically safe. Because the system has no spare capacity in terms of optical power, we detail several design and alignment considerations that aid in maximizing the throughput of the system. We also discuss our protocol for obtaining the spatial and temporal overlap of the signal and pump beams within the Kerr medium, as well as a detailed protocol for spectral acquisition. Finally, we report a few representative results of Raman spectra obtained in the presence of strong fluorescence using our time-gating system.

We discuss the construction and operation of a complex nonlinear optical
system that uses ultrafast all-optical switching to isolate Raman from fluorescence
signals. Using this system we are able to successfully separate Raman and fluorescence
signals utilizing pulse energies and average powers that remain biologically safe.

波谱与自发拉曼显微荧光背景的抑制

Raman spectroscopy is often plagued by a strong fluorescent background, particularly for biological samples. If a sample is excited with a train of ...

科研

生物工程

Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view and for its considerable potential for practical applications. Slow light photonic crystal waveguides, in particular, have played a major part and have been successfully employed for delaying optical signals1-4 and the enhancement of both linear5-7 and nonlinear devices.8-11
Photonic crystal cavities achieve similar effects to that of slow light waveguides, but over a reduced band-width. These cavities offer high Q-factor/volume ratio, for the realization of optically12 and electrically13 pumped ultra-low threshold lasers and the enhancement of nonlinear effects.14-16 Furthermore, passive filters17 and modulators18-19 have been demonstrated, exhibiting ultra-narrow line-width, high free-spectral range and record values of low energy consumption.
To attain these exciting results, a robust repeatable fabrication protocol must be developed. In this paper we take an in-depth look at our fabrication protocol which employs electron-beam lithography for the definition of photonic crystal patterns and uses wet and dry etching techniques. Our optimised fabrication recipe results in photonic crystals that do not suffer from vertical asymmetry and exhibit very good edge-wall roughness. We discuss the results of varying the etching parameters and the detrimental effects that they can have on a device, leading to a diagnostic route that can be taken to identify and eliminate similar issues.
The key to evaluating slow light waveguides is the passive characterization of transmission and group index spectra. Various methods have been reported, most notably resolving the Fabry-Perot fringes of the transmission spectrum20-21 and interferometric techniques.22-25 Here, we describe a direct, broadband measurement technique combining spectral interferometry with Fourier transform analysis.26 Our method stands out for its simplicity and power, as we can characterise a bare photonic crystal with access waveguides, without need for on-chip interference components, and the setup only consists of a Mach-Zehnder interferometer, with no need for moving parts and delay scans.
When characterising photonic crystal cavities, techniques involving internal sources21 or external waveguides directly coupled to the cavity27 impact on the performance of the cavity itself, thereby distorting the measurement. Here, we describe a novel and non-intrusive technique that makes use of a cross-polarised probe beam and is known as resonant scattering (RS), where the probe is coupled out-of plane into the cavity through an objective. The technique was first demonstrated by McCutcheon et al.28 and further developed by Galli et al.29

Use of photonic crystal slow light waveguides and cavities has been widely adopted by the photonics community in many differing applications. Therefore fabrication and characterization of these devices are of great interest. This paper outlines our fabrication technique and two optical characterization methods, namely: interferometric (waveguides) and resonant scattering (cavities).

光子晶体慢光波导和腔体的制备与表征

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view ...

工程学

Measuring Spatially- and Directionally-varying Light Scattering from Biological Material

Light interacts with an organism's integument on a variety of spatial scales. For example in an iridescent bird: nano-scale structures produce color; the milli-scale structure of barbs and barbules largely determines the directional pattern of reflected light; and through the macro-scale spatial structure of overlapping, curved feathers, these directional effects create the visual texture. Milli-scale and macro-scale effects determine where on the organism's body, and from what viewpoints and under what illumination, the iridescent colors are seen. Thus, the highly directional flash of brilliant color from the iridescent throat of a hummingbird is inadequately explained by its nano-scale structure alone and questions remain. From a given observation point, which milli-scale elements of the feather are oriented to reflect strongly? Do some species produce broader "windows" for observation of iridescence than others? These and similar questions may be asked about any organisms that have evolved a particular surface appearance for signaling, camouflage, or other reasons.
In order to study the directional patterns of light scattering from feathers, and their relationship to the bird's milli-scale morphology, we developed a protocol for measuring light scattered from biological materials using many high-resolution photographs taken with varying illumination and viewing directions. Since we measure scattered light as a function of direction, we can observe the characteristic features in the directional distribution of light scattered from that particular feather, and because barbs and barbules are resolved in our images, we can clearly attribute the directional features to these different milli-scale structures. Keeping the specimen intact preserves the gross-scale scattering behavior seen in nature. The method described here presents a generalized protocol for analyzing spatially- and directionally-varying light scattering from complex biological materials at multiple structural scales.

We present a non-destructive method for sampling spatial variation in the direction of light scattered from structurally complex materials. By keeping the material intact, we preserve gross-scale scattering behavior, while concurrently capturing fine-scale directional contributions with high-resolution imaging. Results are visualized in software at biologically-relevant positions and scales.

从生物材料空间定向变化的光散射测量

Light interacts with an organism's integument on a variety of spatial scales. For example in an iridescent bird: nano-scale structures produce color; the ...

Observation and Analysis of Blinking Surface-enhanced Raman Scattering

From a single molecule at a silver nanoaggregate junction, blinking surface-enhanced Raman scattering (SERS) is observed. Here, a protocol is presented on how to prepare the SERS-active silver nanoaggregate, record a video of certain blinking spots in the microscopic image, and analyze the blinking statistics. In this analysis, a power law reproduces the probability distributions for bright events relative to their duration. The probability distributions for dark events are fitted by a power law with an exponential function. The parameters of the power law represent molecular behavior in both bright and dark states. The random walk model and the speed of the molecule across the entire silver surface can be estimated. It is difficult to estimate even when using averages, autocorrelation functions, and super-resolution SERS imaging. In the future, power law analyses should be combined with spectral imaging, because the origins of blinking cannot be confirmed by this analysis method alone.

This protocol describes the analysis of blinking surface-enhanced Raman scattering due to the random walk of a single molecule on a silver surface using power laws.

闪烁表面增强拉曼散射的观测与分析

From a single molecule at a silver nanoaggregate junction, blinking surface-enhanced Raman scattering (SERS) is observed. Here, a protocol is presented on ...

化学

High Speed Sub-GHz Spectrometer for Brillouin Scattering Analysis

The goal of this protocol is to build a parallel high-extinction and high-resolution optical Brillouin spectrometer. Brillouin spectroscopy is a non-contact measurement method that can be used to obtain direct readouts of viscoelastic material properties. It has been a useful tool in material characterization, structural monitoring and environmental sensing. In the past, Brillouin spectroscopy has usually employed scanning Fabry-Perot etalons to perform spectral analysis. This process requires high illumination power and long acquisition times, making the technique unsuitable for biomedical applications. A recently introduced novel spectrometer overcomes this challenge by employing two VIPAs in a cross-axis configuration. This innovation enables sub-Gigahertz (GHz) resolution spectral analysis with sub-second acquisition time and illumination power within the safety limits of biological tissue. The multiple new applications facilitated by this improvement are currently being explored in biological research and clinical application.

Here we present a protocol to build a rapid Brillouin spectrometer. Cascading virtually imaged phase array (VIPA) etalons achieve a measurement speed more than 1,000 times faster than traditional scanning Fabry-Perot spectrometers. This improvement provides the means for Brillouin analysis of tissue and biomaterials at low power levels in vivo.

高速的sub-GHz光谱仪激布里渊散射分析

The goal of this protocol is to build a parallel high-extinction and high-resolution optical Brillouin spectrometer. Brillouin spectroscopy is a ...

Implementation of a Nonlinear Microscope Based on Stimulated Raman Scattering

Stimulated Raman scattering (SRS) microscopy uses near-infrared excitation light; therefore, it shares many multi-photon microscopic imaging properties. SRS imaging modality can be obtained using commercial laser-scanning microscopes by equipping with a non-descanned forward detector with proper bandpass filters and lock-in amplifier (LIA) detection scheme. A schematic layout of a typical SRS microscope includes the following: two pulsed laser beams, (i.e., the pump and probe directed in a scanning microscope), which must be overlapped in both space and time at the image plane, then focused by a microscope objective into the sample through two scanning mirrors (SMs), which raster the focal spot across an x-y plane. After interaction with the sample, transmitted output pulses are collected by an upper objective and measured by a forward detection system inserted in an inverted microscope. Pump pulses are removed by a stack of optical filters, whereas the probe pulses that are the result of the SRS process occurring in the focal volume of the specimen are measured by a photodiode (PD). The readout of the PD is demodulated by the LIA to extract the modulation depth. A two-dimensional (2D) image is obtained by synchronizing the forward detection unit with the microscope scanning unit. In this paper, the implementation of an SRS microscope is described and successfully demonstrated, as well as the reporting of label-free images of polystyrene beads with diameters of 3 &#181;m. It is worth noting that SRS microscopes are not commercially available, so in order to take advantage of these characteristics, the homemade construction is the only option. Since SRS microscopy is becoming popular in many fields, it is believed that this careful description of the SRS microscope implementation can be very useful for the scientific community.

In this manuscript, the implementation of a stimulated Raman scattering (SRS) microscope, obtained by the integration of an SRS experimental set-up with a laser scanning microscope, is described. The SRS microscope is based on two femtosecond (fs) laser sources, a Ti-Sapphire (Ti:Sa) and synchronized optical parametric oscillator (OPO).

基于刺激拉曼散射的非线性显微镜的实现

Stimulated Raman scattering (SRS) microscopy uses near-infrared excitation light; therefore, it shares many multi-photon microscopic imaging properties. ...

Optimizing Brillouin Optical Time-Domain Analyzers Based on Gain Spectrum Engineering

Demonstrated is a unique method for sensing performance enhancement in Brillouin optical time-domain analyzers (BOTDA). A Brillouin gain spectrum (BGS) is superimposed with two symmetric Brillouin loss spectra (BLS). This leads to a complex engineered spectrum shape that is more resistant to the sensing system noise. Instead of only one pump and probe interaction as in the conventional BOTDA setup, three optical probe waves are exploited, with one probe located in the BGS and the other two symmetrically in the BLS. Due to the resistance and insensitivity of the engineered spectrum shape to the noise, the sensing performance is enhanced by 60% and the measurand resolution is doubled.

A protocol for Brillouin optical time-domain analyzers based on gain spectrum engineering is presented. Enhancements in the sensing performance, including sensing range and measurand resolution are achieved and the excess Brillouin intensity noise is studied. The protocol introduces a new way to enhance distributed Brillouin sensing performance.

Demonstrated is a unique method for sensing performance enhancement in Brillouin optical time-domain analyzers (BOTDA). A Brillouin gain spectrum (BGS) is ...

Preparation of Extracellular Matrix Protein Fibers for Brillouin Spectroscopy

Brillouin spectroscopy is an emerging technique in the biomedical field. It probes the mechanical properties of a sample through the interaction of visible light with thermally induced acoustic waves or phonons propagating at a speed of a few km/sec. Information on the elasticity and structure of the material is obtained in a nondestructive contactless manner, hence opening the way to in vivo applications and potential diagnosis of pathology. This work describes the application of Brillouin spectroscopy to the study of biomechanics in elastin and trypsin-digested type I collagen fibers of the extracellular matrix. Fibrous proteins of the extracellular matrix are the building blocks of biological tissues and investigating their mechanical and physical behavior is key to establishing structure-function relationships in normal tissues and the changes which occur in disease. The procedures of sample preparation followed by measurement of Brillouin spectra using a reflective substrate are presented together with details of the optical system and methods of spectral data analysis.

We present a protocol for the application of Brillouin light scattering spectroscopy to elastin and trypsin-purified type I collagen fibers of the extracellular matrix to extract their full elastic properties.

细胞外基质蛋白纤维的布里渊谱的制备

Brillouin spectroscopy is an emerging technique in the biomedical field. It probes the mechanical properties of a sample through the interaction of ...

Multiplex Chemical Imaging Based on Broadband Stimulated Raman Scattering Microscopy

Stimulated Raman scattering (SRS) microscopy is a nonlinear optical technique for label-free chemical imaging. This analytical tool delivers chemical maps at high speed, and high spatial resolution of thin samples by directly interrogating their molecular vibrations. In its standard implementation, SRS microscopy is narrowband and forms images with only a single vibrational frequency at a time. However, this approach not only hinders the chemical specificity of SRS but also neglects the wealth of information encoded within vibrational spectra. 
These limitations can be overcome by broadband SRS, an implementation capable of extracting a vibrational spectrum per pixel of the image in parallel. This delivers hyperspectral data that, when coupled with chemometric analysis, maximizes the amount of information retrieved from the specimen. Thus, broadband SRS improves the chemical specificity of the system, allowing the quantitative determination of the concentration of the different constituents of a sample. Here, we report a protocol for chemical imaging with broadband SRS microscopy, based on a home-built SRS microscope operating with a custom differential multichannel-lock-in amplifier detection. It discusses the sample preparation, alignment of the SRS apparatus, and chemometric analysis. By acquiring vibrational Raman spectra, the protocol illustrates how to identify different chemical species within a mixture, determining their relative concentrations.

We present a protocol to acquire chemical images with broadband stimulated Raman scattering (SRS) microscopy. Based on an SRS microscope that operates with differential multichannel-lock-in detection, the protocol describes the sample preparation, adjustment of the SRS apparatus, and chemometrics to disentangle different constituents of chemically heterogeneous samples.

基于宽带受激拉曼散射显微镜的多重化学成像

Stimulated Raman scattering (SRS) microscopy is a nonlinear optical technique for label-free chemical imaging. This analytical tool delivers chemical maps ...

Direct Comparison of Hyperspectral Stimulated Raman Scattering and Coherent Anti-Stokes Raman Scattering Microscopy for Chemical Imaging

Stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) microscopy are the most widely used coherent Raman scattering imaging technologies. Hyperspectral SRS and CARS imaging offer Raman spectral information at every pixel, which enables better separation of different chemical compositions. Although both techniques require two excitation lasers, their signal detection schemes and spectral properties are quite different. The goal of this protocol is to perform both hyperspectral SRS and CARS imaging on a single platform and compare the two microscopy techniques for imaging different biological samples. The spectral focusing method is employed to acquire spectral information using femtosecond lasers. By using standard chemical samples, the sensitivity, spatial resolution, and spectral resolution of SRS and CARS in the same excitation conditions (i.e., power at the sample, pixel dwell time, objective lens, pulse energy) are compared. The imaging contrasts of CARS and SRS for biological samples are juxtaposed and compared. The direct comparison of CARS and SRS performances would allow for optimal selection of the modality for chemical imaging.

This paper directly compares the resolution, sensitivity, and imaging contrasts of stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) integrated into the same microscope platform. The results show that CARS has a better spatial resolution, SRS gives better contrasts and spectral resolution, and both methods have similar sensitivity.

高光谱受激拉曼散射与相干反斯托克斯拉曼散射显微镜在化学成像中的应用的直接比较

Stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) microscopy are the most widely used coherent Raman scattering imaging ...