Theoretical Nanophysics 11/2023

• neither

• neither

• neither

An SET is said to be in the `quantum dot limit', if ...

• the charging energy dominates the orbital level spacing

• the orbital level spacing dominates the charging energy

• the thermal energy scale dominates the orbital level spacing

• the orbital level spacing dominates the thermal energy scale

In the Anderson model described at the lecture, one (or two) Fermi sea is coupled to...

• a single localized orbital with twofold spin degeneracy

• a localized spin of size 1/2

• a band of acoustic phonons

• impurities, leading to Anderson localisation

In the Kondo model described at the lecture, one (or two) Fermi sea is coupled to...

• a single localised orbital with twofold spin degeneracy

• a localised spin of size 1/2

• a band of acoustic phonons

• impurities, leading to Anderson localisation

At which gate-voltage setting is the Kondo model a reasonable approximation of the Anderson model?

• at the maximum point of a Coulomb peak

• at the slope of a Coulomb peak

• in a Coulomb valley with even occupation

• in a Coulomb valley with odd occupation

How does the spin-spin coupling energy J of the Kondo model scale with the dot-lead tunneling energy t of the Anderson model?

• J ~ t

• J ~ 1/t

• J ~ t²

• J ~ 1/t²

In a quantum dot, the Kondo effect shows the feature that as T -> 0, the linear conductance of the dot ...

• converges to zero

• converges to the conductance quantum

• diverges

• oscillates

• cca. 10 K

• cca. 10 mK

• cca. 10 microkelvin

• cca. 10 nanokelvin