Colloquium
Department of Physics, NCU
Fluctuation and perpetual motion in a nonequilibrium electrical RC circuit
Speaker
Prof. Chen, Yung-Fu (陳永富)
Department of Physics, NCU
Date 2017.02.14(Tue)
Time 14:00
Place S4-625
Abstract:
Learning from remarkable energy-conversion efficiency achieved by bio-molecular machines, heat engines relied on microscopic working substances are suggested for harvesting usable energy (work) from random motion (heat). Feynman ratchet, animaginary ultra-small, asymmetric mechanical device influenced by substantial thermal fluctuation, is proposed to experience perpetual motion to perform work. In this talk I will describe how we realized an electrical version of a Feynman-ratchet-like device via a resistor-capacitor (RC) circuit contact to two different heat baths. Persistent circular motion of a virtual particle buried in incoherent Brownian motion is indeed took place owing to breaking of detailed balance in a nonequilibrium steady state. This experimental demonstration proves the general principle and the possibility of Brownian motors. Schemes of realizing an autonomous heat engine to produce work and for achieving refrigeration will be discussed.