Abstract
We study in experiment and theory thermal energy and charge transfer close to the quantum limit in a ballistic nanodevice, consisting of multiply connected one-dimensional electron waveguides. The fabricated device is based on an AlGaAs/GaAs heterostructure and is covered by a global top-gate to steer the thermal energy and charge transfer in the presence of a temperature gradient, which is established by a heating current. The estimate of the heat transfer by means of thermal noise measurements shows the device acting as a switch for charge and thermal energy transfer. The wave-packet simulations are based on the multi-terminal Landauer-Büttiker approach and confirm the experimental finding of a mode-dependent redistribution of the thermal energy current, if a scatterer breaks the device symmetry.
Highlights
Quantized conductance steps of an electric current through an electron waveguide with a constriction are a hallmark of ballistic transport[1,2,3] and have been successfully modelled within the Landauer-Büttiker approach.[4,5,6] In the ballistic transport theory, the scattering and transmission coefficients of the geometry regulate the flux through the system of non-interacting electrons.Injected electrons inherit the properties of the reservoirs from which they come from and no dephasing or dissipation occurs within the ballistic system
We study in experiment and theory thermal energy and charge transfer close to the quantum limit in a ballistic nanodevice, consisting of multiply connected one-dimensional electron waveguides
The fabricated device is based on an AlGaAs/GaAs heterostructure and is covered by a global top-gate to steer the thermal energy and charge transfer in the presence of a temperature gradient, which is established by a heating current
Summary
Quantized conductance steps of an electric current through an electron waveguide with a constriction are a hallmark of ballistic transport[1,2,3] and have been successfully modelled within the Landauer-Büttiker approach.[4,5,6] In the ballistic transport theory, the scattering and transmission coefficients of the geometry regulate the flux through the system of non-interacting electrons. The presence of junctions and crossings in a multi-terminal device requires to calculate the electric and thermal transport for the specific sample geometry across a range of Fermi energies. This task is facilitated by switching to a time-dependent intermediate representation of the quantum-mechanical transport, using wave packets which are decomposed into plane wave components pointing to the different terminals.[18,19] The theoretical model elucidates the origin of the observed mode-dependent branching ratio of the device[10] by connecting it to specific device imperfections
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.