科学人生◆品味科学分享 http://blog.sciencenet.cn/u/hxiuzhou 中国科学,从此他将伴我一起生活!

博文

冷却大质量物体到量子基态

已有 3056 次阅读 2015-3-23 08:52 |系统分类:论文交流

摘要:将大质量机械振子冷却到基态仍是一个艰巨的任务,因为受到边带不可分辨条件的限制。最近研究人员提出光力诱导透明的冷却方案来实现边带不可分辨条件下的基态冷却,能够将大质量物体冷却到量子基态。这为对大质量宏观机械器件进行量子操控和精密测量提供了途径。

Summary: Ground state cooling of massive mechanical objects remains a difficult task restricted by the unresolved mechanical sidebands. Now researchers have proposed an optomechanically-induced-transparency cooling scheme to achieve ground state cooling of mechanical motion without the resolved sideband condition, capable of cooling massive objects to the quantum ground state. This provides a route for quantum manipulation of massive macroscopic devices and high-precision measurements.

 

 

Cooling of macroscopic and mesoscopic objects to the quantum ground states are of great interests not only for fundamental study of quantum theory but also for the broad applications in quantum information processing and high-precision metrology. However, the cooling limit is subjected to the quantum backaction, and ground state cooling is possible only in the resolved sideband limit, which requires the resonance frequency of the mechanical motion to be larger than the cavity decay rate. This sets a major obstacle for the ground state preparation and quantum manipulation of macroscopic and mesoscopic mechanical resonators, since more massive resonators typically have lower mechanical resonance frequencies. Therefore, it is essential to overcome this limitation, so that ground state cooling can be achieved for massive objects.

 

Very recently, Professor Yun-Feng Xiao and Ph.D student Yong-Chun Liu at Peking University, collaborated with Columbia University, have proposed an unresolved sideband ground-state cooling scheme in a generic optomechanical system, by taking advantage of the destructive quantum interference in a cavity optomechanical system with two mechanical modes coupled to the same optical cavity mode (Figure 1), where optomechanically-induced transparency phenomenon occurs. They find that using the multiple inputs, the cascaded cooling effect further suppresses the quantum backaction heating. They show that ground state cooling of the mechanical mode beyond the resolved sideband limit by nearly three orders of magnitude can be achieved.

Figure 1  An optomechanical system with two mechanical modes coupled to the same optical mode.

 

“This cooling approach adds little complexity to the existing optomechanical system, which is crucial in the experimental point of view.” said Yong-Chun Liu, the first author of the paper. Compared with the conventional backaction cooling approach, the additional requirement here is a control mechanical mode and one (or more) input laser. It is experimentally feasible for various optomechanical systems within current technical conditions. On one hand, many optomechanical systems possess abundant mechanical modes with different resonance frequencies, since the oscillation have different types and orders. This situation can be found in optomechanical systems using whispering-gallery microcavities, photonic crystal cavities, membranes, nanostrings and nanorods amongst others. On the other hand, composite optomechanical systems, containing two independent mechanical resonators, are also conceivable. For example, in Fabry-Perot cavities, the motion of one mirror acts as a control mechanical mode while the other mirror is to be cooled (Figure 1).

 

“This study paves the way for the manipulation of macroscopic mechanical resonators in the quantum regime.” said Yun-Feng Xiao.

 

This research was funded by the National Basic Research Program of China (Grant Nos. 2013CB328704 and 2013CB921904), the National Natural Science Foundation of China (Grant Nos. 11474011, 11222440 and 61435001), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120001110068) and the Optical Radiation Cooling and Heating in Integrated Devices Program of Defense Advanced Research Projects Agency (Grant No. C11L10831).

 

See the article:

Liu Y-C, Xiao Y-F, Luan X-S, et al. Optomechanically-induced-transparency cooling of massive mechanical resonators to the quantum ground state. Sci China-Phys Mech Astron, 2015, 58: 050305, doi: 10.1007/s11433-014-5635-6

http://phys.scichina.com:8083/sciGe/EN/abstract/abstract509634.shtml

 

订阅《中国科学: 物理学 力学 天文学》微信公众号,手机同步关注最新热点文章、新闻、科技资讯, 请添加微信号SCPMA2014或扫描下方图片关注.

 



https://blog.sciencenet.cn/blog-306503-876530.html

上一篇:耦合微腔光力学系统的绝热理论介绍
下一篇:科技期刊六位码编排体系及出版实践
收藏 IP: 219.238.6.*| 热度|

1 wliming

该博文允许注册用户评论 请点击登录 评论 (0 个评论)

数据加载中...
扫一扫,分享此博文

Archiver|手机版|科学网 ( 京ICP备07017567号-12 )

GMT+8, 2024-3-29 21:31

Powered by ScienceNet.cn

Copyright © 2007- 中国科学报社

返回顶部