一、题目：Maxwell's demon in the quantum-Zeno regime and beyond

二、主讲人：Georg Engelhardt

三、时间：2018年4月25日（星期三），下午4:30

四、地点：A4-218 (四友之家)

内容摘要：The Maxwell's demon is a supernatural being which can build a thermal gradient in an ensemble of particles by observing them and applying appropriate feedback actions. As this procedure does not consume energy in the ideal case, this thought experiment is in contradiction with the second law of thermodynamics. Moreover, in quantum mechanics, observations have a central meaning as they are related to a wave-function collapse. Considering a single-electron transistor, where we implement a Maxwell demon by a piecewise-constant feedback protocol, we investigate quantum implications of the Maxwell demon. To this end, we harness a dynamical coarse-graining method, which provides a convenient and accurate description of the system dynamics even for high measurement rates. In doing so, we are able to investigate the Maxwell demon in a quantum-Zeno regime leading to transport blockade. We argue that there is a measurement rate providing an optimal performance. Moreover, we find that besides building up a chemical gradient, there can be also a regime where the feedback loop additionally extracts energy, which results from the energy non-conserving character of the projective measurement.

主讲人简介: Georg Engelhardt，博士，在PRL、PRA等国际著名期刊发表论文多篇。