Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi
Ente Cassa di Risparmio di Firenze (No. 2014.0770A2202.8861)

品質マイクロスフェアの超ファクターの1製作<ol><li>ストリップ光学ストリッパーを使用して、そのアクリルコーティングオフ標準的なシングルモード（SMF）シリカ繊維の約1~2 cmです。 </li><li>アセトンで剥離部分をきれいにし、それを切断します。 </li><li>融着接続機の一方のアームに切断された先端部を導入し、スプライサーコントローラを用いた電気アーク放電のシリーズを生産します。スプライサーコントローラメニューから「手動操作」を選択し、それぞれ、60および800ミリ秒にアーク電力レベルとアーク継続時間の値を設定します。 「アーク」を選択し、下の「+」を押してください。 </li><li>球体が形を取っているしたら、停止、90°繊維を回転させ、ステップ1.3を繰り返します。 </li><li>約160ミクロンのマイクロスフェアを得るために、少なくとも4回繰り返し手順1.3。約260ミクロンのマイクロスフェアを得るために16回繰り返します。 注：電気アーチ放電は、石英ガラスを溶融するために必要な高い溶融温度を生成します。 surfac電子張力はmollifiedファイバ先端からスフェロイドを描画します。それは、図1から 19に見られるように、球のサイズは、約350ミクロンの直径で飽和、アークショットの数に正比例する。回転が共振器の球形を確実にします。 </li></ol> 2.テーパファイバを描きます注：テーパー繊維はまた、微小共振器に光を結合するために必要とされています。ミクロスフェアのサイズは、テーパーの腰部を決定します。球の直径よりも大きく125ミクロンの場合、テーパーの直径は約3-4ミクロンのものとすることができます。小さいもののために、テーパーの直径は小さくする必要があり、1〜2μmで言います。低レベルでの損失を維持するとテーパ部（基本1）に一つだけのモードを持っているために、テーパリングは、（太いから細い直径に徐々に移行）断熱なければなりません。断熱テーパ部の典型的な全長は約2cmである。Figu2再ファイバを引くためホームメイドのデバイスを示し、 図3（a）は 、典型的な腰ゾーンのマイクロフォトを示しています。 <ol><li>ストリップ3-4の光学ストリッパーを使用して、そのアクリルコーティングオフ標準的なシングルモード（SMF）シリカ繊維のCM、およびファイバーレーザー（入力）とパワーメータ（出力）に終了し接続します。ストリッピングゾーンがない一端で、繊維のほぼ中央にあることを確認してください。ファイバーレーザーとパワーメータに終了接続できるようにするために、裸ファイバターミネータを使用します。レーザーと作業台の上に電力計を配置します。 </li><li>引きプロセスの間に同時に作動させる2翻訳段階に短いアルミナシリンダ内取り除か繊維、および繊維のコーティングされた端を置きます。 </li><li>シリカの融点に近い温度（約2100℃）までの酸素ブタン炎によって（つまり、オーブンとして機能する）アルミナシリンダーを加熱します。 </li><li> OBSEからテーパの断熱性を推測します635 nmで動作するレーザ光の透過率のrvation。スクランブルないモードが発生しないことを示す、先細りながら出力で均質な円形スポットが保存されていることを確認してください。引っ張っ停止し、送信された電力は、発振停止したときに炎を引退し、経時的に一定です。 </li><li>テーパを収容するU字状に成形顕微鏡用スライドガラスにテーパファイバを接着（ 図3B参照 ）。 76x26x1.2ミリメートル寸法の顕微鏡スライドガラスを使用してください。 </li></ol>小型マイクロスフェアの3製作注：標準的なファイバのクラッドのサイズ以下の直径を有する小型マイクロスフェアは、繊維の前の先細りを必要とします。この方法を用いて得られた最小直径は約25μmです。 <ol><li>セクション2に従うことによって、それが壊れるまで引っ張って、テーパー状の繊維を描きます。 </li><li>スプライサーの共同で値を変更し、セクション1（UHQ微小球の製造）が、ステップ1.3でのすべての手順に従ってくださいntrollerは以下の通り：アーク電源20、アーク継続時間1200ミリ秒。 </li></ol>マイクロスフェアへ4.カップリングライト注：我々は、マイクロスフェアに結合する光にテーパーを使用して、微小共振器の共振を測定します。 <ol><li> 4.1。真ん中のチャネルとT字型PVC /アルミニウムホルダーを準備します。ホルダーにス​​コッチマジックや紙粘着テープの切れ端でマイクロスフェアの残留繊維ステムを修正しました。圧電アクチュエータと移動ステージと20nmの位置決め分解能に2本のネジでホルダーを固定します。 </li><li>マイクロスフェアの繊維幹に対して垂直に配置スライド面と別の翻訳段階にスライドガラスに接着テーパを修正しました。終端ファイバケーブルにテーパーの端をスプライス。波長可変ダイオードレーザーとInGaAsフォトダイオード検出器に他方に一端を接続します。 </li><li>共同する長作動距離（&gt; 20ミリメートル）と顕微鏡管を使用してくださいテーパーとマイクロスフェアとの間のギャップをntrol。位置微小球の赤道にテーパ相対制御できるようにチューブの方向に対して45°の他の方向の所定の位置にミラーシステムを監視するために。 <ol><li>テーパー状の繊維と接触して、微小球の赤道を置きます。 </li></ol></li><li>レーザーをオンにして、オシロスコープでマイクロスフェアテーパシステムの透過​​スペクトルを確認してください。 <ol><li>共振が現れるまでチューンCWレーザは、1550 nmで動作します。共鳴は、スペクトルにおけるローレンツ形状のディップとして同定することができます。 </li></ol></li><li>共鳴線幅（ローレンツ形ディップの半値幅）を測定します。共鳴線幅で割ったポンプの周波数としてQ値を計算します。 </li><li>球体とテーパとの間のギャップを増加/増大結合効率を低下させるための共鳴幅及び深さの両方を変化させる/減少させます。 </li></ol><pクラス= &quot;jove_title&quot;&gt; 5。誘導ラマン散乱<ol><li> 1550 nmおよび減衰器で動作するCWレーザとの間にエルビウム添加ファイバ増幅器（EDFA）を挿入します。 EDFAは1,530-1,570ナノメートルの波長範囲で動作します。注：これは、高入力パワーを必要とする2 W.非線形効果の最大出力電力に到達し、レーザパワーを後押しする。図4は、実験設定の概略を示しています。 </li><li> 3 dBmのスプリッタに終端ファイバケーブルとテーパーの一方の端を接続します。光スペクトラムアナライザ及びオシロスコープに接続された光検出器の他のいずれかのスプリッタ出力ファイバのいずれかを接続します。 </li><li>レーザの波長スキャン速度に匹敵する熱ドリフトとの共振までチューン低い周波数に高いからレーザーが発見されました。熱セルフロック20が達成されると、共振の広がりは、オシロスコープ上で見ることができます。 </li><li>テーパーを介して送信出力電力をチェック光スペクトラムアナライザに。ラマンレーザーラインが表示されるまで電力を増加させます。これは、約13.5テラヘルツでポンプ波長から離調されています。 </li></ol>

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	<li>Kozyreff, G., Dominguez-Juarez, J. L., Martorell, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non+linear+optics+in+spheres:+from+second+harmonic+scattering+to+quasi-phase+matched+generation+in+whispering+gallery+modes.">Non linear optics in spheres: from second harmonic scattering to quasi-phase matched generation in whispering gallery modes.</a> Laser Photon. Rev. 5 (6), (2011).</li><li>Farnesi, D., Barucci, A., Righini, G. C., Berneschi, S., Soria, S., Nunzi Conti, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+frequency+generation+in+silica+microspheres.">Optical frequency generation in silica microspheres.</a> Phys. Rev. Lett. 112 (9), 093901 (2014).</li><li>Liang, W., 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=Miniature+multioctave+light+source+based+on+a+monolithic+microcavity.">Miniature multioctave light source based on a monolithic microcavity.</a> Optica. 2 (1), 40-47 (2015).</li><li>Maker, A. J., Armani, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+of+Silica+Ultra+High+Quality+Factor+Microresonators.">Fabrication of Silica Ultra High Quality Factor Microresonators.</a> J. Vis. Exp. (65), e4164 (2012).</li><li>Coillet, A., Henriet, R., Phan Huy, K., Jacquot, M., Furfaro, L., Balakireva, I., 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=Microwave+Photonics+Systems+Based+on+Whispering-gallery-mode+Resonators.">Microwave Photonics Systems Based on Whispering-gallery-mode Resonators.</a> J. Vis. Exp. (78), e50423 (2013).</li><li>Han, K., Kim, K. H., Kim, J., Lee, W., Liu, J., Fan, X., 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=Fabrication+and+Testing+of+Microfluidic+Optomechanical+Oscillators.">Fabrication and Testing of Microfluidic Optomechanical Oscillators.</a> J. Vis. Exp. (87), e51497 (2014).</li><li>Arnold, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microspheres,+Photonic+Atoms,+and+the+Physics+of+Nothing.">Microspheres, Photonic Atoms, and the Physics of Nothing.</a> American Scientist. 89 (5), 414-421 (2001).</li><li>Chiasera, A., 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=Spherical+whispering+gallery+mode+microresonators.">Spherical whispering gallery mode microresonators.</a> Laser Photon. Rev. 4 (3), 457-482 (2010).</li><li>Helt, L. G., Liscidini, M., Sipe, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+does+it+scale?+Comparing+quantum+and+classical+nonlinear+optical+processes+in+integrated+devices.">How does it scale? Comparing quantum and classical nonlinear optical processes in integrated devices.</a> J. Opt. Soc. Am. B. 29 (8), 2199-2212 (2012).</li><li>Leach, D. H., Chang, R. K., Acker, W. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stimulated+anti-Stokes+Raman+scattering+in+microdroplets.">Stimulated anti-Stokes Raman scattering in microdroplets.</a> Opt. Lett. 17 (6), 387-389 (1992).</li><li>Farnesi, D., Cosi, F., Trono, C., Righini, G. C., Nunzi Conti, G., Soria, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stimulated+Antistokes+Raman+scattering+resonantly+enhanced+in+silica+microspheres.">Stimulated Antistokes Raman scattering resonantly enhanced in silica microspheres.</a> Opt. Lett. 39 (20), 5993-5996 (2014).</li><li>Qian, S. X., Chang, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiorder+Stokes+emission+from+micrometer+size+droplets.">Multiorder Stokes emission from micrometer size droplets.</a> Phys. Rev. Lett. 56 (9), 926-929 (1986).</li><li>Lin, H. B., Campillo, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CW+nonlinear+optics+in+droplet+microcavities+displaying+enhanced+gain.">CW nonlinear optics in droplet microcavities displaying enhanced gain.</a> Phys. Rev. Lett. 73 (18), 2440-2443 (1994).</li><li>Spillane, S. M., Kippenberg, T. J., Vahala, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultralow+threshold+Raman+laser+using+a+spherical+dielectric+microcavity.">Ultralow threshold Raman laser using a spherical dielectric microcavity.</a> Nature. 415 (6872), 621-623 (2002).</li><li>Kippenberg, T. J., Spillane, S. M., Vahala, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kerr-Nonlinearity+optical+parametrical+oscillation+in+an+ultrahigh+Q+toroid+microcavity.">Kerr-Nonlinearity optical parametrical oscillation in an ultrahigh Q toroid microcavity.</a> Phys. Rev. Lett. 93 (8), 083904 (2004).</li><li>Hill, S. C., Leach, D. H., Chang, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Third+order+sum+frequency+generation+in+droplets:+model+with+numerical+results+for+third-harmonic+generation.">Third order sum frequency generation in droplets: model with numerical results for third-harmonic generation.</a> J. Opt. Soc. Am. B. 10 (1), 16-33 (1993).</li><li>Kozyreff, G., Dominguez Juarez, J. L., Martorell, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whispering+gallery+mode+phase+matching+for+surface+second+order+nonlinear+optical+processes+in+spherical+microresonators.">Whispering gallery mode phase matching for surface second order nonlinear optical processes in spherical microresonators.</a> Phys. Rev. A. 77 (4), 043817 (2008).</li><li>Jouravlev, M. V., Kurizki, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unified+theory+of+Raman+and+parametric+amplification+in+nonlinear+microspheres.">Unified theory of Raman and parametric amplification in nonlinear microspheres.</a> Phys. Rev. A. 70 (5), 053804 (2004).</li><li>Brenci, M., Calzolai, R., Cosi, F., Nunzi Conti, G., Pelli, S., Righini, 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=Microspherical+resonators+for+biophotonic+sensors.">Microspherical resonators for biophotonic sensors.</a> Proc. SPIE. 6158, 61580S (2006).</li><li>Carmon, T., Yang, L., Vahala, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamical+thermal+behavior+and+thermal+self-stability+of+microcavities.">Dynamical thermal behavior and thermal self-stability of microcavities.</a> Opt. Express. 12 (20), 4742-4750 (2004).</li><li>Kippenberg, T. J., Spillane, S. M., Min, B., Vahala, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theoretical+and+experimental+study+of+stimulated+and+cascaded+Raman+scattering+in+ultrahigh+Q+optical+microcavities.">Theoretical and experimental study of stimulated and cascaded Raman scattering in ultrahigh Q optical microcavities.</a> J. Sel. Quantum Electron. 10 (5), 1219-1228 (2004).</li><li>Bloembergen, N., Shen, Y. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupling+between+vibrations+and+light+waves+in+Raman+laser+media.">Coupling between vibrations and light waves in Raman laser media.</a> Phys. Rev. Lett. 12 (18), 504-507 (1964).</li><li>Gorodestky, M. L., Pryamikov, A. D., Ilchenko, V. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rayleigh+scattering+in+high+Q+microspheres.">Rayleigh scattering in high Q microspheres.</a> J. Opt. Soc. Am. B. 17 (6), 1051-1057 (2000).</li><li>Arnold, S., Ramjit, R., Keng, D., Kolchenko, V., Teraoka, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microparticle+photophysics+illuminates+viral+bio-sensing.">Microparticle photophysics illuminates viral bio-sensing.</a> Faraday Discuss. 137, 65-83 (2008).</li><li>Ozdemir, S. K., 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=Highly+sensitive+detection+of+nanoparticle+with+a+self+referenced+and+self-heterodyned+whispering+gallery+Raman+microlaser.">Highly sensitive detection of nanoparticle with a self referenced and self-heterodyned whispering gallery Raman microlaser.</a> Proc. Natl. Acad. Sci USA. 11 (37), E3836-E3844 (2014).</li></ol>

The authors declare that they have no competing financial interests. D.F. is a PhD student at the University of Parma.

マイクロスフェアは、コンパクトで効率的な非線形振動子であり、彼らは製造、取り扱いが非常に簡単です。テーパー付き繊維は、結合共振器/からの光を抽出するために使用することができます。 95％までの共鳴造影約3×10 8のQ値を得ることができます。 これらの製造技術の主な制限は、大量生産との統合です。繊維の清潔さは、マイクロスフェアとテーパーの...

ウィスパリングギャラリーモード共振器（WGMR）は非線形現象1-3のしきい値の低減を可能にする2つのユニークな特性、長い光子寿命と小さなモード体積を示しています。ウィスパリングギャラリーモードは、全内部反射によって誘電空気界面に閉じ込められる光モードです。一時的な閉じ込めは、空洞の品質係数Qに関連しているのに対し、小モード容積は、高い空間閉じ込めによるものです。 WGMRは異なる形状を持つことができ、高Q共振器をこのような高品質係数に変換する原子スケールの粗さ、近くにシリカマイクロスフィアの展示など4-6表面張力の空洞を得るのに適した別の製造技術があります。閉じ込めの両方のタイプは大幅にWGMR内部に強力なエネルギーの蓄積に起因する非線形効果のしきい値を減らします。また、連続波（CW）非線形光学を可能にします。 WGMRは番目を使用して記述することができます水素原子7との強い類似の電子の量子数nは、L、M、およびそれらの偏光状態、。球対称は、半径方向と角度依存性で分離することを可能にします。ラジアル溶液はベッセル関数、球面調和8による角度のものによって与えられます。 シリカガラスは、したがって、Χに関連する二次現象は（2）の相互作用が禁止され、中心対称であると。ミクロスフェアの表面に、対称性の反転が破壊され、Χ（2）の現象は、1観察することができます。しかし、二次周波数発生に対する位相整合条件は、関与する波長が非常に異なっており、分散の役割が非常に重要であり得るので、特に、三次周波数発生における等価より問題です。二次相互作用は非常に弱いです。一方、THIのためのQ 3で生成された電力の鱗そのため番目の注文の相互作用Q 4。9で生成された電力の鱗、この作業の焦点は、三次光学非線形感受率であるΧような誘導ラマン散乱（SRS）と刺激Antistokesラマン散乱（SARS）など（3）相互作用、SARS少ない探求相互作用10,11です。チャン12とカミーロ13は、高非線形WGMRなどの材料が、ポンプレーザではなくCWのパルス化されたの液滴を用いた非線形現象の研究を開拓してきました。シリカマイクロスフィア14,10とマイクロトロイド15は、過去数十年間で注目の多くを得て、マイクロ液滴に比べて、より安定かつ堅牢なプラットフォームを提供します。特に、シリカマイクロスフィアは、製造、取り扱いが非常に簡単です。 SRSは、閾値に到達すると十分であるため、容易に、シリカWGMR 14,15で達成することができる純粋なゲイン処理です。この場合、高circulatiWGMR内部強度をngのは、ラマンレーザー発振を保証しますが、パラメトリック発振のために十分ではありません。これらのケースでは、効率的な振動は、エネルギーと運動量保存則と16-18を成就するすべての共振モードの良い空間的な重なり、位相およびモード整合を必要とします。これは、一般的にはSARSとFWMの場合です。

<table><tbody><tr><td>Optical Fiber</td><td>Corning</td><td>SMF28</td><td></td></tr><tr><td>Fiber coating stripper</td><td>Thorlabs</td><td>T06S13</td><td>Available from other vendors as well</td></tr><tr><td>Fiber cleaver</td><td>Fitel</td><td>S325A</td><td>Available from other vendors as well</td></tr><tr><td>Fusion splicer</td><td>Furakawa</td><td>S177A-1R</td><td>Available from other vendors as well</td></tr><tr><td>Butane and Oxygen Gas</td><td>n/a</td><td></td><td>any vendor</td></tr><tr><td>Microscope tube</td><td>Navitar</td><td>Zoom 6000</td><td>Modular Kit</td></tr><tr><td>CCD camera</td><td>n/a</td><td>N/A</td><td>any will fit</td></tr><tr><td>Monitor</td><td>n/a</td><td>N/A</td><td>any monitor is valid</td></tr><tr><td>3-Axis Stage</td><td>PI Instruments, Thorlabs, Melles</td><td></td><td></td></tr><tr><td>Assorted posts and mounts</td><td>Thorlabs</td><td></td><td>Available from other vendors as well</td></tr><tr><td>Polarization control</td><td>Thorlabs</td><td>FPC030</td><td>Available from other vendors as well</td></tr><tr><td>Attenuator</td><td>Throlabs</td><td>VOA50</td><td></td></tr><tr><td>Photodiode</td><td>Thorlabs</td><td>PDA400</td><td>discontinued, replaced by PDA10CS-EC</td></tr><tr><td>Oscilloscope</td><td>Tektronix</td><td>DPO7104</td><td></td></tr><tr><td>Optical spectrum analyzer</td><td>Ando</td><td>AQ6317B</td><td></td></tr><tr><td>Erbium Doped Fiber Amplifier</td><td>IPG Photonics</td><td>EAD-2K-C</td><td></td></tr><tr><td>Tunable Laser</td><td>Yenista</td><td>TUNICS</td><td></td></tr></tbody></table>

stimulated stokes and antistokes raman scattering in microspherical whispering gallery mode resonators

誘電体微小球は、高品質係数ウィスパリングギャラリーモードを介して、時間の長さ（WGM）のために、光と音を閉じ込めることができます。コンパクトなレーザ光源、高感度生化学センサーおよび非線形現象：ガラス微小球は、アプリケーションの巨大な様々なエネルギーのストアとして考えることができます。微小球と連結システムの両方を製造するためのプロトコルが与えられます。ここで説明するカプラーはテーパー状繊維です。三次光学非線形感受率に関連する非線形現象を効率的に生成するには、Χは（3）三重共鳴シリカマイクロスフィアにおける相互作用は、この論文で提示されています。誘導ラマン散乱（SRS）、および4波が刺激アンチストークスラマン散乱（SARS）を含む混合プロセス：ここで報告相互作用があります。キャビティ強化現象の証拠は、ポンプ、信号およびアイドラー間の相関の欠如によって与えられる共振モードがペアを得るために存在しなければなりません信号およびアイドラーの。 hyperparametric振動の場合（4波混合と刺激アンチストークスラマン散乱）では、モードは、エネルギーと運動量保存を果たすと、最後のではなく、少なくともを、良い空間的な重なりを持っている必要があります。

マイクロスフェアのQファクタは、プロトコルが、上記の大口径のための10 8（ 図5）（&gt; 200ミクロン）を超えると小さい直径のため10 6（&lt;50ミクロン）を超えている以下の作製しました。 95％の上記共鳴コントラスト（臨界結合に近い）を容易に観察することができます。高い循環強度のために、赤外領域の次の非線形効果を観察するこ...

Watch this Scientific Journal Video about Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators at JoVE.com

Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators

微小球ウィスパリングギャラリーモード共振器で刺激ストークスとAntistokesラマン散乱

三次光学非線形感受率に関連する非線形現象を効率的に生成するには、Χは（3）三重共鳴シリカマイクロスフィアにおける相互作用は、この論文で提示されています。誘導ラマン散乱（SRS）、および4波が刺激アンチストークスラマン散乱（SARS）を含む混合プロセス：ここで報告相互作用があります。

Dielectric microspheres can confine light and sound for a length of time through high quality factor whispering gallery modes (WGM). Glass microspheres ...

stimulated-stokes-antistokes-raman-scattering-microspherical

Universidad San Sebastian

Research

JoVE Journal

Engineering

11.2K ビュー.  Enrico Fermi Center. 三次光学非線形感受率に関連する非線形現象を効率的に生成するには、Χは（3）三重共鳴シリカマイクロスフィアにおける相互作用は、この論文で提示されています。誘導ラマン散乱（SRS）、および4波が刺激アンチストークスラマン散乱（SARS）を含む混合プロセス：ここで報告相互作用があります。 

ビデオ: Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators

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.

共鳴と自発ラマン顕微の蛍光バックグラウンドの除去

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

生物工学

Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors

Optical modes of dielectric micro-cavities have received significant attention in recent years for their potential in a broad range of applications. The optical modes are frequently referred to as "whispering gallery modes" (WGM) or "morphology dependent resonances" (MDR) and exhibit high optical quality factors. Some proposed applications of micro-cavity optical resonators are in spectroscopy1, micro-cavity laser technology2, optical communications3-6 as well as sensor technology. The WGM-based sensor applications include those in biology7, trace gas detection8, and impurity detection in liquids9. Mechanical sensors based on microsphere resonators have also been proposed, including those for force10,11, pressure12, acceleration13 and wall shear stress14. In the present, we demonstrate a WGM-based electric field sensor, which builds on our previous studies15,16. A candidate application of this sensor is in the detection of neuronal action potential.
The electric field sensor is based on polymeric multi-layered dielectric microspheres. The external electric field induces surface and body forces on the spheres (electrostriction effect) leading to elastic deformation. This change in the morphology of the spheres, leads to shifts in the WGM. The electric field-induced WGM shifts are interrogated by exciting the optical modes of the spheres by laser light. Light from a distributed feedback (DFB) laser (nominal wavelength of ~ 1.3 &mu;m) is side-coupled into the microspheres using a tapered section of a single mode optical fiber. The base material of the spheres is polydimethylsiloxane (PDMS). Three microsphere geometries are used: (1) PDMS sphere with a 60:1 volumetric ratio of base-to-curing agent mixture, (2) multi layer sphere with 60:1 PDMS core, in order to increase the dielectric constant of the sphere, a middle layer of 60:1 PDMS that is mixed with varying amounts (2% to 10% by volume) of barium titanate and an outer layer of 60:1 PDMS and (3) solid silica sphere coated with a thin layer of uncured PDMS base. In each type of sensor, laser light from the tapered fiber is coupled into the outermost layer that provides high optical quality factor WGM (Q ~ 106). The microspheres are poled for several hours at electric fields of ~ 1 MV/m to increase their sensitivity to electric field.

A high-sensitivity photonic micro sensor was developed for electric field detection. The sensor exploits the optical modes of a dielectric sphere. Changes in the external electric field perturb the sphere morphology leading to shifts in its optical modes. The electric field strength is measured by monitoring these optical shifts.

ギャラリーモード高分子マイクロ光電界センサを囁くの開発

Optical modes of dielectric micro-cavities have received significant attention in recent years for their potential in a broad range of applications. The ...

工学

Microwave Photonics Systems Based on Whispering-gallery-mode Resonators

Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency.

The customized techniques developed in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators are presented. The protocols to obtain and characterize these resonators are detailed, and an explanation of some of their applications in microwave photonics is given.

ウィスパリングギャラリーモード共振器に基づいたマイクロ波フォトニクスシステム

Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various ...

Fabrication and Testing of Microfluidic Optomechanical Oscillators

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including microresonators. However, because of the increased acoustic radiative losses during direct liquid immersion of optomechanical devices, almost all published optomechanical experiments have been performed in solid phase. This paper discusses a recently introduced hollow microfluidic optomechanical resonator. Detailed methodology is provided to fabricate these ultra-high-Q microfluidic resonators, perform optomechanical testing, and measure radiation pressure-driven breathing mode and SBS-driven whispering gallery mode parametric vibrations. By confining liquids inside the capillary resonator, high mechanical- and optical- quality factors are simultaneously maintained.

Parametric optomechanical excitations have recently been experimentally demonstrated in microfluidic optomechanical resonators by means of optical radiation pressure and stimulated Brillouin scattering. This paper describes the fabrication of these microfluidic resonators along with methodologies for generating and verifying optomechanical oscillations.

作製とマイクロ流体光力学発振器のテスト

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including ...

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems

This paper briefly describes how nanowires with diameters corresponding to 1 to 5 atoms can be produced by melting a range of inorganic solids in the presence of carbon nanotubes. These nanowires are extreme in the sense that they are the limit of miniaturization of nanowires and their behavior is not always a simple extrapolation of the behavior of larger nanowires as their diameter decreases. The paper then describes the methods required to obtain Raman spectra from extreme nanowires and the fact that due to the van Hove singularities that 1D systems exhibit in their optical density of states, that determining the correct choice of photon excitation energy is critical. It describes the techniques required to determine the photon energy dependence of the resonances observed in Raman spectroscopy of 1D systems and in particular how to obtain measurements of Raman cross-sections with better than 8% noise and measure the variation in the resonance as a function of sample temperature. The paper describes the importance of ensuring that the Raman scattering is linearly proportional to the intensity of the laser excitation intensity. It also describes how to use the polarization dependence of the Raman scattering to separate Raman scattering of the encapsulated 1D systems from those of other extraneous components in any sample.

The paper describes a method for producing extreme nanowires by melt infiltration into carbon nanotubes and how 1D systems may be characterized and investigated using Resonance Raman Spectroscopy to determine vibrational and optical excitation energies.

エクストリームナノワイヤおよびその他の1D系の共鳴ラマン分光

This paper briefly describes how nanowires with diameters corresponding to 1 to 5 atoms can be produced by melting a range of inorganic solids in the ...

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

Recent years have witnessed a significant increase in the use of spontaneous Brillouin spectrometers for non-contact analysis of soft matter, such as aqueous solutions and biomaterials, with fast acquisition times. Here, we discuss the assembly and operation of a Brillouin spectrometer that uses stimulated Brillouin scattering (SBS) to measure stimulated Brillouin gain (SBG) spectra of water and lipid emulsion-based tissue-like samples in transmission mode with &lt;10 MHz spectral-resolution and &lt;35 MHz Brillouin-shift measurement precision at &lt;100 ms. The spectrometer consists of two nearly counter-propagating continuous-wave (CW) narrow-linewidth lasers at 780 nm whose frequency detuning is scanned through the material Brillouin shift. By using an ultra-narrowband hot rubidium-85 vapor notch filter and a phase-sensitive detector, the signal-to-noise-ratio of the SBG signal is significantly enhanced compared to that obtained with existing CW-SBS spectrometers. This improvement enables measurement of SBG spectra with up to 100-fold faster acquisition times, thereby facilitating high spectral-resolution and high-precision Brillouin analysis of soft materials at high speed.

We describe the construction of a rapid continuous-wave-stimulated-Brillouin-scattering (CW-SBS) spectrometer. The spectrometer employs single-frequency diode-lasers and an atomic vapor notch-filter to acquire transmission spectra of turbid/non-turbid samples with high spectral-resolution at speeds up to 100-fold faster than those of existing CW-SBS spectrometers. This improvement enables high-speed Brillouin material analysis.

材料の分析のための高速連続誘導ブリルアン散乱分光器

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

Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, interface precipitation, and mini-emulsion. In all methods, well-defined, micrometer-sized spheres are obtained from a self-assembling process in solution. The vapor diffusion method can result in spheres with the highest sphericity and surface smoothness, yet the types of the polymers able to form these spheres are limited. On the other hand, in the mini-emulsion method, microspheres can be made from various types of polymers, even from highly crystalline polymers with coplanar, &#960;-conjugated backbones. The photoluminescent (PL) properties from single isolated microspheres are unusual: the PL is confined inside the spheres, propagates at the circumference of the spheres via the total internal reflection at the polymer/air interface, and self-interferes to show sharp and periodic resonant PL lines. These resonating modes are so-called "whispering gallery modes" (WGMs). This work demonstrates how to measure WGM PL from single isolated spheres using the micro-photoluminescence (&#181;-PL) technique. In this technique, a focused laser beam irradiates a single microsphere, and the luminescence is detected by a spectrometer. A micromanipulation technique is then used to connect the microspheres one by one and to demonstrate the intersphere PL propagation and color conversion from coupled microspheres upon excitation at the perimeter of one sphere and detection of PL from the other microsphere. These techniques, &#181;-PL and micromanipulation, are useful for experiments on micro-optic application using polymer materials.

Protocols for the synthesis of microspheres from polymers, the manipulation of microspheres, and micro-photoluminescence measurements are presented.

光共振器およびレーザ応用のためのポリマーマイクロスフェアの作製

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, ...

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).

刺激されたラマン散乱に基づく非線形顕微鏡の実施

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

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional &#960;-conjugate Systems

Femtosecond time-resolved stimulated Raman spectroscopy is a promising method of observing the structural dynamics of short-lived transients with near infrared (near-IR) transitions, because it can overcome the low sensitivity of spontaneous Raman spectrometers in the near-IR region. Here, we describe technical details of a femtosecond time-resolved near-IR multiplex stimulated Raman spectrometer that we have recently developed. A description of signal generation and optimization, measurement, data acquisition, and calibration and correction of recorded data is provided as well. We present an application of our spectrometer to analyze the excited-state dynamics of &#946;-carotene in toluene solution. A C=C stretch band of &#946;-carotene in the second lowest excited singlet (S2) state and the lowest excited singlet (S1) state is clearly observed in the recorded time-resolved stimulated Raman spectra. The femtosecond time-resolved near-IR stimulated Raman spectrometer is applicable to the structural dynamics of &#960;-conjugate systems from simple molecules to complex materials.

Details of signal generation and optimization, measurement, data acquisition, and data handling for a femtosecond time-resolved near-IR stimulated Raman spectrometer are described. A near infrared stimulated Raman study on the excited-state dynamics of &#946;-carotene in toluene is shown as a representative application.

超高速時間分解型近IR刺激型機能π共役システムのラマン測定

Femtosecond time-resolved stimulated Raman spectroscopy is a promising method of observing the structural dynamics of short-lived transients with near ...

化学

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.

広帯域刺激ラマン散乱顕微鏡に基づく多重化学イメージング

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