Dynamics of a quantum oscillator strongly and off-resonantly coupled with a two-level system

Dynamics of a quantum oscillator strongly and off-resonantly coupled with a two-level system

Beyond the rotating-wave approximation, the dynamics of a quantum oscillator interacting strongly and off-resonantly with a two-level system exhibit beatings, whose period equals the revival time of the two-level system. On a longer time scale, the quantum oscillator shows collapses, revivals and fractional revivals, which are encountered in oscillator observables like the mean number of oscill...

Dynamics of a two-level system strongly coupled to a high-frequency quantum oscillator

E. K. Irish,1,2,* J. Gea-Banacloche,3 I. Martin,4 and K. C. Schwab2 1Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA 2Laboratory for Physical Sciences, 8050 Greenmead Drive, College Park, Maryland 20740, USA 3Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA 4Theoretical Division, Los Alamos National Laboratory, Los Ala...

Dynamics of a two-level system coupled to a quantum oscillator: Transformed rotating-wave approximation

For studying the dynamics of a two-level system coupled to a quantum oscillator we have presented an analytical approach, the transformed rotating-wave approximation, which takes into account the effect of the counter-rotating terms but still keeps the simple mathematical structure of the ordinary rotating-wave approximation. We have calculated the energy levels of ground and lower-lying excite...

State-dependent impedance of a strongly coupled oscillator-qubit system

Decoherence dynamics of a qubit coupled to a quantum two-level system

We study the decoherence dynamics of a qubit coupled to a quantum two-level system (TLS) in addition to its weak coupling to a background environment. We analyze the different regimes of behaviour that arise as the values of the different parameters are varied. We classify those regimes as two weak-coupling regimes, which differ by the relation between the qubit and TLS decoherence times, and a...