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QmeQ 1.0 : An open-source Python package for calculations of transport through quantum dot devices

Kirsanskas, Gediminas LU ; Pedersen, Jonas Nyvold LU ; Karlström, Olov LU ; Leijnse, Martin LU and Wacker, Andreas LU (2017) In Computer Physics Communications 221. p.317-342
Abstract

QmeQ is an open-source Python package for numerical modeling of transport through quantum dot devices with strong electron-electron interactions using various approximate master equation approaches. The package provides a framework for calculating stationary particle or energy currents driven by differences in chemical potentials or temperatures between the leads which are tunnel coupled to the quantum dots. The electronic structures of the quantum dots are described by their single-particle states and the Coulomb matrix elements between the states. When transport is treated perturbatively to lowest order in the tunneling couplings, the possible approaches are Pauli (classical), first-order Redfield, and first-order von Neumann master... (More)

QmeQ is an open-source Python package for numerical modeling of transport through quantum dot devices with strong electron-electron interactions using various approximate master equation approaches. The package provides a framework for calculating stationary particle or energy currents driven by differences in chemical potentials or temperatures between the leads which are tunnel coupled to the quantum dots. The electronic structures of the quantum dots are described by their single-particle states and the Coulomb matrix elements between the states. When transport is treated perturbatively to lowest order in the tunneling couplings, the possible approaches are Pauli (classical), first-order Redfield, and first-order von Neumann master equations, and a particular form of the Lindblad equation. When all processes involving two-particle excitations in the leads are of interest, the second-order von Neumann approach can be applied. All these approaches are implemented in QmeQ. We here give an overview of the basic structure of the package, give examples of transport calculations, and outline the range of applicability of the different approximate approaches. Program summary: Program Title: QmeQ Program Files doi: http://dx.doi.org/10.17632/8687mrhgg9.1 Licensing provisions: BSD 2-Clause. Programming language: Python External libraries: NumPy, SciPy, Cython Nature of problem: Calculation of stationary state currents through quantum dots tunnel coupled to leads. Solution method: Exact diagonalization of the quantum dot Hamiltonian for a given set of single particle states and Coulomb matrix elements. Numerical solution of the stationary-state master equation for a given approximate approach. Restrictions: Depending on the approximate approach the temperature needs to be sufficiently large compared to the coupling strength for the approach to be valid.

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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Anderson-type model, Coulomb blockade, Open quantum systems, Python, Quantum dots
in
Computer Physics Communications
volume
221
pages
317 - 342
publisher
Elsevier
external identifiers
  • scopus:85028709688
  • wos:000413376800026
ISSN
0010-4655
DOI
10.1016/j.cpc.2017.07.024
language
English
LU publication?
yes
id
84c96ac0-a691-48ad-bbe0-71a432878cc7
alternative location
https://arxiv.org/abs/1706.10104
date added to LUP
2017-09-27 14:51:48
date last changed
2019-03-19 03:40:05
@article{84c96ac0-a691-48ad-bbe0-71a432878cc7,
  abstract     = {<p>QmeQ is an open-source Python package for numerical modeling of transport through quantum dot devices with strong electron-electron interactions using various approximate master equation approaches. The package provides a framework for calculating stationary particle or energy currents driven by differences in chemical potentials or temperatures between the leads which are tunnel coupled to the quantum dots. The electronic structures of the quantum dots are described by their single-particle states and the Coulomb matrix elements between the states. When transport is treated perturbatively to lowest order in the tunneling couplings, the possible approaches are Pauli (classical), first-order Redfield, and first-order von Neumann master equations, and a particular form of the Lindblad equation. When all processes involving two-particle excitations in the leads are of interest, the second-order von Neumann approach can be applied. All these approaches are implemented in QmeQ. We here give an overview of the basic structure of the package, give examples of transport calculations, and outline the range of applicability of the different approximate approaches. Program summary: Program Title: QmeQ Program Files doi: http://dx.doi.org/10.17632/8687mrhgg9.1 Licensing provisions: BSD 2-Clause. Programming language: Python External libraries: NumPy, SciPy, Cython Nature of problem: Calculation of stationary state currents through quantum dots tunnel coupled to leads. Solution method: Exact diagonalization of the quantum dot Hamiltonian for a given set of single particle states and Coulomb matrix elements. Numerical solution of the stationary-state master equation for a given approximate approach. Restrictions: Depending on the approximate approach the temperature needs to be sufficiently large compared to the coupling strength for the approach to be valid.</p>},
  author       = {Kirsanskas, Gediminas and Pedersen, Jonas Nyvold and Karlström, Olov and Leijnse, Martin and Wacker, Andreas},
  issn         = {0010-4655},
  keyword      = {Anderson-type model,Coulomb blockade,Open quantum systems,Python,Quantum dots},
  language     = {eng},
  month        = {08},
  pages        = {317--342},
  publisher    = {Elsevier},
  series       = {Computer Physics Communications},
  title        = {QmeQ 1.0 : An open-source Python package for calculations of transport through quantum dot devices},
  url          = {http://dx.doi.org/10.1016/j.cpc.2017.07.024},
  volume       = {221},
  year         = {2017},
}