Local effective dynamics of quantum systems: A generalized approach to work and heat
Abstract
By computing the local energy expectation values with respect to some local measurement basis we show that for any quantum system there are two fundamentally different contributions: changes in energy that do not alter the local von Neumann entropy and changes that do. We identify the former as work and the latter as heat. Since our derivation makes no assumptions on the system Hamiltonian or its state, the result is valid even for states arbitrarily far from equilibrium. Examples are discussed ranging from the classical limit to purely quantummechanical scenarios, i.e. where the Hamiltonian and the density operator do not commute.
 Publication:

EPL (Europhysics Letters)
 Pub Date:
 August 2008
 DOI:
 10.1209/02955075/83/30008
 arXiv:
 arXiv:0708.2354
 Bibcode:
 2008EL.....8330008W
 Keywords:

 Quantum Physics;
 Condensed Matter  Statistical Mechanics
 EPrint:
 5 pages, 1 figure, published version