Stub model for dephasing in a quantum dot

Details Stub model for dephasing in a quantum dot Stub model for dephasing in a quantum dot

2005-03-14

arxiv.org/abs/cond-mat/0503347v1

Journal of Physics A 38, 10639 (2005).

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

8 pages with 1 figure; contribution for the special issue of J.Phys.A on "Trends in Quantum Chaotic Scattering"

Scientific paper

10.1088/0305-4470/38/49/011

As an alternative to Buttiker's dephasing lead model, we examine a dephasing stub. Both models are phenomenological ways to introduce decoherence in chaotic scattering by a quantum dot. The difference is that the dephasing lead opens up the quantum dot by connecting it to an electron reservoir, while the dephasing stub is closed at one end. Voltage fluctuations in the stub take over the dephasing role from the reservoir. Because the quantum dot with dephasing lead is an open system, only expectation values of the current can be forced to vanish at low frequencies, while the outcome of an individual measurement is not so constrained. The quantum dot with dephasing stub, in contrast, remains a closed system with a vanishing low-frequency current at each and every measurement. This difference is a crucial one in the context of quantum algorithms, which are based on the outcome of individual measurements rather than on expectation values. We demonstrate that the dephasing stub model has a parameter range in which the voltage fluctuations are sufficiently strong to suppress quantum interference effects, while still being sufficiently weak that classical current fluctuations can be neglected relative to the nonequilibrium shot noise.

Affiliated with

Also associated with

No associations

Rating

Stub model for dephasing in a quantum dot 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 Stub model for dephasing in a quantum dot, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stub model for dephasing in a quantum dot will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-316047