Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

A General Formalism for Continuous Feedback Control in Quantum Systems

Annby-Andersson, Björn LU (2022)
Abstract
This thesis devolops a general formalism for continuous feedback control in quantum systems. The main result is a quantum Fokker-Planck master equation describing the joint dynamics of a quantum system and a detector with finite bandwidth. For a fast detector, this equation can be reduced to a Markovian master equation for the system dynamics. In particular, the formalism is amenable to analytical treatments of feedback protocols that depend nonlinearly on the measured signal. Previously, only numerical methods were available for this. We apply the formalism on two toy models to highlight its usefuleness. We find that the formalism provides insight into the connection between thermodynamics and information theory.
Abstract (Swedish)
This thesis develops a general formalism for continuous feedback control in quantum systems. The main result is a quantum Fokker-Planck master equation describing the joint dynamics of a quantum system and a detector with finite bandwidth. For a fast detector, this equation can be reduced to a Markovian master equation for the system dynamics. In particular, the formalism is amenable to analytical treatments of feedback protocols that depend nonlinearly on the measured signal. Previously, only numerical methods were available for this. We apply the formalism on two toy models to highlight its usefulness. We find that the formalism provides insight into the connection between thermodynamics and information theory.
Please use this url to cite or link to this publication:
author
supervisor
organization
publishing date
type
Thesis
publication status
published
subject
keywords
quantum measurements, quantum control, stochastic thermodynamics, information thermodynamics, full count- ing statistics, open quantum systems, Quantum measurements, Quantum control, Stochastic thermodynamics, Information thermodynamics, Full counting statistics, Open quantum systems
pages
146 pages
publisher
Lund University
ISBN
978-91-8039-371-3
978-91-8039-372-0
language
English
LU publication?
yes
id
e5d54eca-baf3-4850-8db1-3c89aa44a68e
date added to LUP
2022-10-24 13:48:05
date last changed
2022-10-31 13:16:18
@misc{e5d54eca-baf3-4850-8db1-3c89aa44a68e,
  abstract     = {{This thesis devolops a general formalism for continuous feedback control in quantum systems. The main result is a quantum Fokker-Planck master equation describing the joint dynamics of a quantum system and a detector with finite bandwidth. For a fast detector, this equation can be reduced to a Markovian master equation for the system dynamics. In particular, the formalism is amenable to analytical treatments of feedback protocols that depend nonlinearly on the measured signal. Previously, only numerical methods were available for this. We apply the formalism on two toy models to highlight its usefuleness. We find that the formalism provides insight into the connection between thermodynamics and information theory.}},
  author       = {{Annby-Andersson, Björn}},
  isbn         = {{978-91-8039-371-3}},
  keywords     = {{quantum measurements, quantum control, stochastic thermodynamics, information thermodynamics, full count- ing statistics, open quantum systems; Quantum measurements; Quantum control; Stochastic thermodynamics; Information thermodynamics; Full counting statistics; Open quantum systems}},
  language     = {{eng}},
  month        = {{08}},
  note         = {{Licentiate Thesis}},
  publisher    = {{Lund University}},
  title        = {{A General Formalism for Continuous Feedback Control in Quantum Systems}},
  url          = {{https://lup.lub.lu.se/search/files/126598780/LicThesisFinal.pdf}},
  year         = {{2022}},
}