Complete positivity, finite-temperature effects, and additivity of noise for time-local qubit dynamics
: Juho Lankinen, Henri Lyyra, Boris Sokolov, Jose Teittinen, Babak Ziaei, and Sabrina Maniscalco
Publisher: American Phyiscal Society
: 2016
: Physical Review A
: Phys. Rev. A
: 052103
: 93
: 5
: 6
: 2469-9926
: 2469-9934
DOI: https://doi.org/10.1103/PhysRevA.93.052103
: http://journals.aps.org/pra/abstract/10.1103/PhysRevA.93.052103
We present a general model of qubit dynamics which entails pure
dephasing and dissipative time-local master equations. This allows us to
describe the combined effect of thermalization and dephasing beyond the
usual Markovian approximation. We investigate the complete positivity
conditions and introduce a heuristic model that is always physical and
provides the correct Markovian limit. We study the effects of
temperature on the non-Markovian behavior of the system and show that
the noise additivity property discussed by Yu and Eberly [Phys. Rev. Lett. 97, 140403 (2006)] holds beyond the Markovian limit.
