Advanced

Thermoelectric transport and thermometry of quantum dots

Josefsson, Martin LU (2015) PHYM01 20151
Department of Physics
Solid State Physics
Abstract
Thermoelectricity is the physical principle of converting heat energy directly into electrical energy. Devices based on this principle so far fall short on efficiency but future thermoelectric devices based on QDs can have very high efficiency. Before QDs can be used in actual devices their behavior must the studied to a further extent. This work theoretically explores how a QD in a single electron transistor setup can be characterized from thermoelectric measurements. It is shown how asymmetric tunnel couplings between the QD and the leads, the temperatures of the leads and an applied magnetic field will influence the thermocurrent (electrical current generated by a temperature difference) through the dot.
This work also contains... (More)
Thermoelectricity is the physical principle of converting heat energy directly into electrical energy. Devices based on this principle so far fall short on efficiency but future thermoelectric devices based on QDs can have very high efficiency. Before QDs can be used in actual devices their behavior must the studied to a further extent. This work theoretically explores how a QD in a single electron transistor setup can be characterized from thermoelectric measurements. It is shown how asymmetric tunnel couplings between the QD and the leads, the temperatures of the leads and an applied magnetic field will influence the thermocurrent (electrical current generated by a temperature difference) through the dot.
This work also contains comparisons of a Landauer-Büttiker and a Master equation approach to calculate the current through the QD. For the Master equation approach both infinite lifetime sequential tunneling and a lifetime broadening utilizing Lorentzian distribution functions to account for the widths of the energy levels are used. It is found that the broadening is important to include when calculating the thermopower but it fails at calculating the heat current. (Less)
Please use this url to cite or link to this publication:
author
Josefsson, Martin LU
supervisor
organization
course
PHYM01 20151
year
type
H2 - Master's Degree (Two Years)
subject
keywords
thermoelectricity, quantum dot, QD, quantum transport, solid state physics
language
English
id
7358233
date added to LUP
2015-06-18 12:18:22
date last changed
2015-06-18 12:18:22
@misc{7358233,
  abstract     = {Thermoelectricity is the physical principle of converting heat energy directly into electrical energy. Devices based on this principle so far fall short on efficiency but future thermoelectric devices based on QDs can have very high efficiency. Before QDs can be used in actual devices their behavior must the studied to a further extent. This work theoretically explores how a QD in a single electron transistor setup can be characterized from thermoelectric measurements. It is shown how asymmetric tunnel couplings between the QD and the leads, the temperatures of the leads and an applied magnetic field will influence the thermocurrent (electrical current generated by a temperature difference) through the dot.
This work also contains comparisons of a Landauer-Büttiker and a Master equation approach to calculate the current through the QD. For the Master equation approach both infinite lifetime sequential tunneling and a lifetime broadening utilizing Lorentzian distribution functions to account for the widths of the energy levels are used. It is found that the broadening is important to include when calculating the thermopower but it fails at calculating the heat current.},
  author       = {Josefsson, Martin},
  keyword      = {thermoelectricity,quantum dot,QD,quantum transport,solid state physics},
  language     = {eng},
  note         = {Student Paper},
  title        = {Thermoelectric transport and thermometry of quantum dots},
  year         = {2015},
}