20th RQC Seminar
Dr. Alessandro Ferreri
(Postdoctoral Researcher, Research center “Forschungszentrum” Jülich, Germany）
ハイブリッド（Zoom ・ 理研 和光事業所 統合支援棟2階 大会議室）
Quantum thermodynamics of optomechanical systems in the nonlinear regimes
Confining quantum fields by means of specific boundary conditions offers a higher degree of manipulation with respect to free field systems. As an example, boundary conditions can refer to the presence of a cavity, whose both geometry and dynamics determine the structure of the field modes . An interesting case thereof consists in controlling the position of one of the two cavity walls by means of an external drive. In this framework, the cavity itself works as a quantum piston, which confines the quantum field, and whose volume is controlled by the drive. The evident analogy of this system with a classical piston containing a gas provides a good prompt for the investigation of the thermodynamic features of optomechanical system. This talk is structured in three parts. In the first part, an innovative protocol to quantize the system field-wall is presented. Interestingly, this procedure does not require the introduction of the time-dependency into the equation of motion, and it spontaneously provides both the optomechanical coupling and the excitation transfer between the field and the wall . In the second part, concepts of quantum thermodynamics are reviewed. Specific attention will be paid to both the role of thermal engines in a quantum regime , and the formalism to describe out-of-equilibrium processes . Finally, the last part of the talk is dedicated to the current effort at investigating optomechanical systems through the lens of quantum thermodynamics.
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