Effective Theory of Electron-Hole Exchange in Semiconductor Quantum Dots

Short-range versus long-range electron-hole exchange interactions in semiconductor quantum dots

Using a many-body approach based on atomistic pseudopotential wave functions we show that the electronhole exchange interaction in semiconductor quantum dots is characterized by a large, previously neglected long-range component, originating from monopolar interactions of the transition density between different unit cells. The calculated electron-hole exchange splitting of CdSe and InP nanocry...

Asymmetric exchange between electron spins in coupled semiconductor quantum dots

Strong electron-hole exchange in coherently coupled quantum dots.

We have investigated few-body states in vertically stacked quantum dots. Because of a small interdot tunneling rate, the coupling in our system is in a previously unexplored regime where electron-hole exchange plays a prominent role. By tuning the gate bias, we are able to turn this coupling off and study a complementary regime where total electron spin is a good quantum number. The use of diff...

New Theoretical Approach to Quantum Size Effects of Interactive Electron-hole in Spherical Semiconductor Quantum Dots

The issue of quantum size effects of interactive electron-hole systems in spherical semiconductor quantum dots is put to question. A sharper theoretical approach is suggested based on a new pseudo-potential method. In this new setting, analytical computations can be performed in most intermediate steps lending stronger support to the adopted physical assumptions. The resulting numerical values ...

Electron-hole crossover in graphene quantum dots.

We investigate the addition spectrum of a graphene quantum-dot in the vicinity of the electron-hole crossover as a function of perpendicular magnetic field. Coulomb-blockade resonances of the 50 nm wide dot are visible at all gate voltages across the transport gap ranging from hole to electron transport. The magnetic field dependence of more than 50 states displays the unique complex evolution ...