Quantum Optomechanics on Multiple Mass Scales

多质量尺度的量子光力学

• 批准号: 1707840
• 负责人: Nergis Mavalvala
• 金额: $ 75万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707840&HistoricalAwards=false
• 关键词: Quantum; Optomechanics; Multiple; Mass; Scales

The motion of everyday objects like humans, tennis balls and cars is very well described by the the laws of classical mechanics, first laid out by Isaac Newton. But the microscopic world of atoms and their constituent particles is more accurately described by quantum mechanics. These two regimes of physics - classical and quantum - are well understood, but what happens at the boundary between the two regimes? Is there even a clear, well-defined boundary? When does an object transition from classical to quantum behavior? And why should we care? Scientists have come to understand that quantum behavior is present in objects of all sizes, shapes and compositions, but is usually masked by thermal noise - the constant jittering of atoms that make up the objects due to heat energy stored and released. Removing thermal noise to reveal quantum mechanical behavior is very difficult even for a small collection of atoms, and certainly very hard for much larger objects. But it can be done, initially just for a few special atoms, and recently for increasingly larger objects. Macroscopic objects that exhibit quantum behavior are useful not only for studying the classical-quantum boundary, but also have some very practical applications. Among these applications is generating exotic quantum states of light, called "squeezed" states, that can be used to make more precise measurements than ordinary light. Interferometric gravitational wave detectors, such as the Advance LIGO ones that discovered gravitational waves from colliding black holes, rely on measuring the positions of mirrors with sub-attometer (less than one billionth of a billionth of a meter) precision. To further improve their sensitivity, one can inject squeezed states of light into these instruments. This work pertains to making these special states of light by strongly coupling laser light to movable mirrors whose motion is dominated by quantum mechanical effects rather than thermal noise. To make a squeezed state, it is necessary to find a way to correlate two usually uncorrelated properties of the light - a combination of the amplitude and phase. This is usually done by passing light through a nonlinear optical material whose refractive index depends on the strength of the electric field (amplitude of the light), such that amplitude fluctuations get imprinted on the phase of the light as it passes through that material. In this work the PI uses an alternative, and relatively unexplored, method of using optomechanical coupling. An intense light beam is incident on a movable mirror. The amplitude fluctuations of the light drive the mirror position due to radiation pressure. The mirror position fluctuations are imprinted on the phase of the light reflected from the mirror, thus correlating amplitude and phase fluctuations. The setup comprises an optical cavity where one mirror is a nano-fabricated cantilevered oscillator made of a GaAlAs heterostructure Bragg reflector. The other mirror is ablated and coated on to an optical fiber tip. The aim is to generate squeezed light in a broad audio frequency band using this apparatus. To do so, it is necessary to reduce the thermal noise of the mirror oscillator enough for its motion to be dominated by quantum fluctuations, which requires a highly optimized oscillator design that may also be cryogenic cooled. As with any quantum-limited experiment, a variety of other classical noises, such as seismic and acoustic vibrations, classical intensity and phase noise of the optical system must be reduced and controlled.

艾萨克·牛顿（Isaac Newton）首先阐述的古典力学定律，如人类，网球和汽车等日常物体的运动得到了很好的描述。但是，量子力学更准确地描述了原子及其成分颗粒的微观世界。这两个物理学制度 - 古典和量子 - 是充分理解的，但是两个制度之间的边界会发生什么？甚至还有一个清晰，明确的边界吗？物体从经典行为何时过渡？我们为什么要关心？科学家已经了解到，量子行为存在于各种尺寸，形状和成分的物体中，但通常被热噪声掩盖 - 由于存储和释放热能而导致物体的原子的持续抖动。消除热噪声以揭示量子机械行为，即使对于一小部分原子来说，也很难，对于更大的物体而言，当然也很难。但这可以做到，最初仅用于一些特殊的原子，而最近才是越来越大的物体。表现出量子行为的宏观物体不仅可用于研究经典量子边界，而且还具有一些非常实用的应用。在这些应用中，生成了奇特的光量子状态，称为“挤压”状态，可用于比普通光进行更精确的测量。干涉引力波检测器，例如从碰撞黑洞发现引力波的前进凸轮探测器，依赖于测量具有子点功能计（少于十亿分之一米的十亿分之一）精度的镜子位置。为了进一步提高其敏感性，可以将挤压光态注入这些仪器中。这项工作与通过将激光光与可移动的镜子强烈耦合，其运动以量子机械效应而不是热噪声为主导的可移动镜子，这与使这些特殊的光状态有关。要使挤压状态，有必要找到一种方法来关联两个通常不相关的光的特性 - 振幅和相位的组合。这通常是通过将光穿过非线性光学材料来完成的，该光学材料的折射率取决于电场的强度（光的振幅），从而使幅度波动在光线通过该材料时的阶段被印在光相。在这项工作中，PI使用了使用光力耦合的替代方法，相对尚未探索的方法。强烈的灯光光束入射在可移动的镜子上。由于辐射压力，光的幅度波动驱动镜像位置。镜像的位置波动印在反射镜反射的光的相位，从而将振幅和相位波动相关联。该设置包括一个光腔，其中一镜是由Gaalas异质结构Bragg反射器制成的纳米制造的悬臂振荡器。 另一个镜子被烧蚀并涂在光纤尖端上。目的是使用此设备在广泛的音频频带中产生挤压光。为此，有必要将镜像振荡器的热噪声降低足够多，以使其运动以量子波动为主导，这需要高度优化的振荡器设计，这也可能是低温冷却的。与任何量子限制的实验一样，必须降低和控制光学系统的经典强度和相位噪声等各种其他经典噪声，例如地震和声学振动。

项目成果

Approaching the motional ground state of a 10-kg object

• DOI: 10.1126/science.abh2634
• 发表时间: 2021-02
• 期刊: Science
• 影响因子: 56.9
• 作者: C. Whittle;E. Hall;S. Dwyer;N. Mavalvala;V. Sudhir;R. Abbott;A. Ananyeva;C. Austin;L. Barsotti;J. Betzwieser;C. Blair;A. Brooks;D. Brown;A. Buikema;C. Cahillane;J. Driggers;A. Effler;Á. Fernández-Galiana;P. Fritschel;V. Frolov;T. Hardwick;M. Kasprzack;K. Kawabe;N. Kijbunchoo;J. Kissel;G. Mansell;F. Matichard;L. McCuller;T. McRae;A. Mullavey;A. Pele;R. Schofield;D. Sigg;M. Tse;G. Vajente;D. Vander-Hyde;Hang Yu;Haocun Yu;C. Adams;R. Adhikari;S. Appert;K. Arai;J. Areeda;Y. Asali;S. Aston;A. Baer;M. Ball;S. Ballmer;S. Banagiri;D. Barker;J. Bartlett;B. Berger;D. Bhattacharjee;G. Billingsley;S. Biscans;R. Blair;N. Bode;P. Booker;R. Bork;A. Bramley;K. Cannon;X. Chen;A. Ciobanu;F. Clara;C. Compton;S. Cooper;K. Corley;S. Countryman;P. Covas;D. Coyne;L. Datrier;D. Davis;C. D. Fronzo;K. Dooley;P. Dupej;T. Etzel;M. Evans;T. Evans;J. Feicht;P. Fulda;M. Fyffe;J. Giaime;K. Giardina;P. Godwin;E. Goetz;S. Gras;C. Gray;R. Gray;A. Green;E. Gustafson;R. Gustafson;J. Hanks;J. Hanson;R. Hasskew;M. Heintze;A. Helmling-Cornell;N. Holland;J. Jones;S. Kandhasamy;S. Karki;P. King;Rahul Kumar;M. Landry;B. Lane;B. Lantz;M. Laxen;Y. Lecoeuche;J. Leviton;J. Liu;M. Lormand;A. Lundgren;R. Macas;M. Macinnis;D. Macleod;S. M'arka;Z. M'arka;D. Martynov;K. Mason;T. Massinger;R. McCarthy;D. McClelland;S. Mccormick;J. McIver;G. Mendell;K. Merfeld;E. Merilh;F. Meylahn;T. Mistry;R. Mittleman;G. Moreno;C. Mow-Lowry;S. Mozzon;T. Nelson;P. Nguyen;L. Nuttall;J. Oberling;R. Oram;C. Osthelder;D. Ottaway;H. Overmier;J. R. Palamos;W. Parker;E. Payne;R. Penhorwood;C. Perez;M. Pirello;H. Radkins;K. Ramirez;J. Richardson;K. Riles;N. Robertson;J. Rollins;C. Romel;J. Romie;M. Ross;K. Ryan;T. Sadecki;E. Sanchez;L. Sanchez;T. R. Saravanan;R. Savage;D. Schaetzl;R. Schnabel;E. Schwartz;D. Sellers;T. Shaffer;B. Slagmolen;J. R. Smith;S. Soni;B. Sorazu;A. Spencer;K. Strain;L. Sun;M. J. Szczepa'nczyk;M. Thomas;P. Thomas;K. Thorne;K. Toland;C. Torrie;G. Traylor;A. Urban;G. Valdes;P. Veitch;K. Venkateswara;Gautam Venugopalan;A. Viets;T. Vo;C. Vorvick;M. Wade;R. Ward;J. Warner;B. Weaver;R. Weiss;B. Willke;C. Wipf;L. Xiao;H. Yamamoto;L. Zhang;M. Zucker;J. Zweizig

Sub-hertz optomechanically induced transparency with a kilogram-scale mechanical oscillator

• DOI: 10.1103/physreva.100.013853
• 发表时间: 2018-12
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: T. Bodiya;V. Sudhir;C. Wipf;N. Smith;A. Buikema;A. Kontos;Hang Yu;N. Mavalvala

Radiation-pressure-mediated control of an optomechanical cavity

• DOI: 10.1103/physreva.97.013827
• 发表时间: 2018-01-18
• 期刊: PHYSICAL REVIEW A
• 影响因子: 2.9
• 作者: Cripe, Jonathan;Aggarwal, Nancy;Corbitt, Thomas
• 通讯作者: Corbitt, Thomas

Room-temperature optomechanical squeezing

• DOI: 10.1038/s41567-020-0877-x
• 发表时间: 2020-07-01
• 期刊: NATURE PHYSICS
• 影响因子: 19.6
• 作者: Aggarwal, Nancy;Cullen, Torrey J.;Mavalvala, Nergis
• 通讯作者: Mavalvala, Nergis

Measurement of quantum back action in the audio band at room temperature

• DOI: 10.1038/s41586-019-1051-4
• 发表时间: 2019-04-18
• 期刊: NATURE
• 影响因子: 64.8
• 作者: Cripe, Jonathan;Aggarwal, Nancy;Corbitt, Thomas
• 通讯作者: Corbitt, Thomas