ECNU makes important achievements in cavity optomechanics


The research team, led by Prof. Wu Haibin from the State Key Laboratory of Precision Spectroscopy of ECNU, has demonstrated that heat can be transmitted a long distance through the optical field, a new mechanism of heat transmission, and also discovered that the second law of thermodynamics can be violated under nonequilibrium steady states, thus moving an important step forward towards the efficient utilization of all optical controlled devices, quantum heat engines and energies. The results, titled “Phonon heat transport in cavity-mediated optomechanical nanoresonators”, were published in Nature Communications on September 16, 2020, with East China Normal University as the completion institute, PhD candidate Yang Cheng as the first author and researcher Sheng Jiteng, a Zijiang Youth Talent, and Prof. Wu Haibin as the corresponding authors.

Thermal energy can be transmitted in three ways, namely, convection, conduction and radiation. These are all heat transmissions from the macroscopic perspective, that is, to transmit and move fluid atoms or molecules mainly through different temperatures. But when the size of the system is reduced to microns and nanometers, some striking phenomena have been revealed in random and quantum fluctuations.

Based on the regime of long-range nanomechanical resonators with optomechanical coupling, the research team has realized a new mechanism of long-range controlled heat transmission different from the traditional mechanisms, and discovered the phenomenon of heat flux oscillating back and forth. In addition, the team also studied the probability density function of heat flux on the basis of non-equilibrium thermodynamics, which first demonstrated the highest precision of nonequilibrium steady-state heat flux density with experiments, and verified the thermodynamic uncertainty relation that is universal but vital for future small-scale devices.

Cavity optomechanics, the focus of the research team, is an important research frontier of science, which is promising in implementing precision measurement of quantum sensing, micro-nano photonics, quantum devices, etc., and also provides a novel way to verify the basic problems of quantum mechanics on a macro scale, making itself an ideal research platform for insights into the essence of microscopic matters and connection with the macroscopic world. 

This work has been funded by the Photon Regulation Key Program of the Ministry of Science and Technology, the Key Program of the National Natural Science Foundation of China, the National Science Fund for Distinguished Young Scholars and the Shanghai Major Fundamental Research Program.

Refer to

Source:the State Key Laboratory of Precision Spectroscopy of ECNU

Copyeditor: Philip Nash

Editor: Zhang Linlan


East China Normal University