Realizing fast temperature measurement and simulating Maxwell's demon with nearly nondestructive detection in cold atoms  

作　　者：XIN WANG YUAN SUN LIANG LIU 

机构地区：[1]CAS Key Laboratory of Quantum Optics and Center of Cold Atom Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Photonics Research》2022年第8期1947-1955,共9页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(92165107);National Key Research and Development Program of China(2016YFA0301504)。

摘　　要：Optical detection and manipulation of the thermal properties is an essential subject of cold atoms in the quantum era. For laser cooled alkali atoms, we have experimentally realized deterministic temperature measurement with time cost below 1 ms and effective filtering of colder atoms with temperature less than 1 μK, with the help of nearly nondestructive detection. The quick temperature measurement is accomplished by carefully resolving the diffusion dynamics of atoms with the information provided by a single probe laser pulse in the form of bucket detection, while suppressing the amplitude and phase noises of probe laser. The separation of colder atoms is attainable as the velocity differences of atoms translate into nontrivial position differences, when the diffusion sustains for a few tens of milliseconds. In particular, these efforts are based on a labeling process that distinguishes the cold atoms under study from the others by specific internal states, while the nearly nondestructive detection is implemented via driving a cycling transition with continuous optical pulses. Moreover, such a position-dependent labeling process can be further modified to become velocity-dependent, with which we have demonstrated a Maxwell’s demon-type operation on cold atoms, as Maxwell’s demon’s intricate abilities can be understood as measuring the velocity of an individual particle and then performing feedback according to a straightforward dichotomy of the velocity value.

关 键 词：MAXWELL TRANSLATE STRAIGHT 

分 类 号：O562[理学—原子与分子物理]