CMT seminar: Testing quantum adiabaticity with quench echo

Wednesday, May 9, 2012 – 2:00pm – 3:00pm
Reiss 502
Haitao Quan
Department of Physics, University of Maryland

Adiabaticity of quantum evolution is important in many settings; one example is the adiabatic quantum computation (AQC). Nevertheless, to date, there is no effective method available for testing the adiabaticity of the evolution for the case where the eigenenergies of the driven Hamiltonian are not known. We propose a simple method for checking adiabaticity of a quantum process for an arbitrary quantum system. We further propose an operational method for finding more efficient protocols that approximate adiabaticity, and suggest a “uniformly adiabatic” quench scheme based on the Kibble-Zurek mechanism for the case where the initial and the final Hamiltonians are given. This method should help in implementing AQC and other tasks where preserving the system in the ground state of a time-dependent Hamiltonian is desired.

Host: Jim Freericks