Dresden 2009 – scientific programme

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DY: Fachverband Dynamik und Statistische Physik

DY 23: Statistical physics far from thermal equilibrium

DY 23.1: Invited Talk

Thursday, March 26, 2009, 14:00–14:30, HÜL 386

Work and Fluctuation Theorems for quantum systems — •Peter Talkner — Inst. fuer Physik, Universitaet Augsburg, Germany

For small systems classical work and fluctuation theorems have proved useful to extract thermodynamic information from nonequilibrium processes. Here, we focus on specific quantum aspects of work performed on a quantum system by an external force. This work is random due to the randomness of quantum mechanics and of the initial state. The statistics of work is completely determined by its characteristic function defined as Fourier transform of the corresponding probability. This characteristic function can be expressed in terms of a correlation function of exponentiated system's Hamiltonians at the two instants of times that mark the beginning and end of the force protocol [1]. For systems that initially stay in a canonical state Jarzynski's work theorem [1] and Tasaki-Crooks' fluctuation theorem [2] follow immediately. For a microcanonical initial state a Crooks type fluctuation theorem holds [3]. The dependence of the statistics of work on the force protocol and the initial state are exemplified for a driven harmonic oscillator [4]. Generalizations of fluctuation and work theorems to open systems[5] are mentioned. [1] P. Talkner, E. Lutz, and P. Hanggi, Phys. Rev. E 75, 050102(R) (2007). [2]P. Talkner, and P. Hanggi, J. Phys. A 49, F569 (2007). [3] P. Talkner, M. Morillo, and P. Hanggi,Phys. Rev. E 77, 051131 (2008). [4] P. Talkner, P.S. Burada, and P. Hanggi, Phys. Rev. E 78, 011115 (2008). [5] P. Talkner, M. Campisi, and P. Hanggi, J. Stat. Mech. Theor. Exp. in press; arXiv:0811.0973.