Charge and energy transport in time-dependently driven electron - - PowerPoint PPT Presentation

Charge and energy transport in time-dependently driven electron systems

Janine Splettstößer Applied Quantum Physics, MC2, Chalmers University of Technology

College on Energy Transport and Energy Conversion in the Quantum Regime ICTP Trieste, August 2019

Charge and energy transport in time-dependently driven electron systems

(ohio.edu)

Quantum-dot systems

Discrete spectrum!

L R

RWTH Aachen (Stampfer) U Lund (Xu) U Würzburg (Molenkamp)

Quantum-dot systems

Transport spectroscopy — single-electron transistor

L R

RWTH Aachen (Stampfer) U Lund (Xu) U Würzburg (Molenkamp)

Quantum-dot systems

Transport spectroscopy — single-electron transistor

L R

RWTH Aachen (Stampfer) U Lund (Xu) U Würzburg (Molenkamp)

Quantum-dot systems

Transport spectroscopy — single-electron transistor

L R

RWTH Aachen (Stampfer) U Lund (Xu) U Würzburg (Molenkamp)

Decay of charge and energy from a dot after a (potential) switch (Example 2)

see, e.g., N. Ubbelohde, et al.: Nat. Nanotechnol. 10, 46 (2015);

How is energy transferred/dissipated in time-dependent systems?

◮ Heat current → two modes, second can dominate the heat decay:

IQ = ace−γct + ape−γpt

◮ γp depends on bare coupling only and is the biggest rate ◮

Signatures

• f

attractive Coulomb interaction

)

• U

0 − µ

• 1
• 0.5

0.5 1 ap/(UΓ)

−U/2

• J. Schulenborg, R. B. Saptsov, F. Haupt, J. Splettstoesser, M. R. Wegewijs: Phys. Rev. B 93, 081411 (2016); J. Schulenborg, A. Di Marco,
• J. Vanherck, M. R. Wegewijs, J. Splettstoesser: Entropy 19, 668 (2017); J. Schulenborg, J. Splettstoesser, M. R. Wegewijs: Phys. Rev. B

98, 235405 (2018).

Double dot pump - Carnot heat engine (Example 1)

◮ Working principle of the double-dot cyclic heat engine

time-dependent coupling and decoupling to heat baths

◮ Similarities and differences with the classical counterpart

• S. Juergens, F. Haupt, M. Moskalets, J. Splettstoesser: Phys. Rev. B 87, 245423 (2013)