Work Measurement as a Generalized Quantum Measurement

2 11/2015

Monday, 02 Nov. 2015, 11:00 - 12:00

Presenter: Juan Pablo Paz; Departamento de Física, Universidad de Buenos Aires, Argentina
Host: I. Fuentes
Where: Ernst-Mach-Lecture Hall, 2nd Floor, Boltzmanngasse 5, 1090 Wien

I will discuss some recent developments on quantum thermodynamics and present a new method to measure the work on a driven quantum system. The method is based on a simple fact that remained unnoticed until recently: Work on a quantum system can be measured by performing a generalized quantum measurement at a single time. Such measurement, a POVM, reduces to an ordinary projective measurement on an enlarged system. This observation not only demystifies work measurement but also suggests a new quantum algorithm to efficiently sample the work distribution. This can be used, in combination with fluctuation theorems, to estimate free energies of quantum states on a quantum computer. I will discuss some ideas on how to implement this scheme in a realistic experiment with ensembles of cold atoms.