Bipolar Quantum Trajectory Methods

We revisit the stochastic master equation approach to feedback cooling of a quantum mechanical oscillator undergoing position measurement. By introducing a rotating wave approximation for the measurement and bath coupling, we can provide a more intuitive analysis of the achievable cooling in various regimes of measurement sensitivity and temperature. We also discuss explicitly the effect of backaction noise on the characteristics of the optimal feedback. The resulting rotating wave master equation has found application in our recent work on squeezing the oscillator motion using parametric driving and may have wider interest.

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Quantum trajectory simulations of two-state behavior in an optical cavity containing one atom

Physical Review A ◽

10.1103/physreva.46.r6801 ◽

1992 ◽

Vol 46 (11) ◽

pp. R6801-R6804 ◽

Cited By ~ 176

Author(s):

L. Tian ◽

H. J. Carmichael

Keyword(s):

Optical Cavity ◽

Quantum Trajectory ◽

State Behavior ◽

Trajectory Simulations

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Estimation of the Ground State Energy of an Atomic Solid by Employing Quantum Trajectory Dynamics with Friction

Journal of Chemical Theory and Computation ◽

10.1021/ct501176m ◽

2015 ◽

Vol 11 (7) ◽

pp. 2891-2899 ◽

Cited By ~ 15

Author(s):

Bing Gu ◽

Robert J. Hinde ◽

Vitaly A. Rassolov ◽

Sophya Garashchuk

Keyword(s):

Ground State Energy ◽

Ground State ◽

State Energy ◽

Quantum Trajectory ◽

Trajectory Dynamics

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THE QUANTUM TRAJECTORY APPROACH TO GEOMETRIC PHASE FOR OPEN SYSTEMS

Modern Physics Letters A ◽

10.1142/s0217732305017718 ◽

2005 ◽

Vol 20 (22) ◽

pp. 1635-1654 ◽

Cited By ~ 4

Author(s):

ANGELO CAROLLO

Keyword(s):

Quantum System ◽

Open System ◽

Geometric Phase ◽

Open Systems ◽

Quantum Trajectory ◽

Operational Method ◽

Markovian Approximation ◽

Physical Systems ◽

Quantum Jump ◽

Trajectory Approach

The quantum jump method for the calculation of geometric phase is reviewed. This is an operational method to associate a geometric phase to the evolution of a quantum system subjected to decoherence in an open system. The method is general and can be applied to many different physical systems, within the Markovian approximation. As examples, two main source of decoherence are considered: dephasing and spontaneous decay. It is shown that the geometric phase is to very large extent insensitive to the former, i.e. it is independent of the number of jumps determined by the dephasing operator.

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