Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact

Details Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact

2011-01-12

arxiv.org/abs/1101.2393v1

Phys. Rev. B 83, 115439 (2011). (note of Ref.76 added in the published version)

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

Accepted for publication in Physical Review B (20 pages, 13 figures)

Scientific paper

10.1103/PhysRevB.83.115439

We study the dynamics of a nanomechanical resonator (NMR) subject to a measurement by a low transparency quantum point contact (QPC) or tunnel junction in the non-Markovian domain. We derive the non-Markovian number-resolved (conditional) and unconditional master equations valid to second order in the tunneling Hamiltonian without making the rotating-wave approximation and the Markovian approximation, generally made for systems in quantum optics. Our non-Markovian master equation reduces, in appropriate limits, to various Markovian versions of master equations in the literature. We find considerable difference in dynamics between the non-Markovian cases and its Markovian counterparts. We also calculate the time-dependent transport current through the QPC which contains information about the measured NMR system. We find an extra transient current term proportional to the expectation value of the symmetrized product of the position and momentum operators of the NMR. This extra current term, with a coefficient coming from the combination of the imaginary parts of the QPC reservoir correlation functions, has a substantial contribution to the total transient current in the non-Markovian case, but was generally ignored in the studies of the same problem in the literature. Considering the contribution of this extra term, we show that a significantly qualitative and quantitative difference in the total transient current between the non-Markovian and the Markovian wide-band-limit cases can be observed. Thus, it may serve as a witness or signature of the non-Markovian features in the coupled NMR-QPC system.

Affiliated with

Also associated with

No associations

Rating

Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-Markovian dynamics of a nanomechanical resonator measured by a quantum point contact will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-265413