Spin exciton in a quantum dot with spin-orbit coupling at high magnetic field
Physical Review B
Coulomb interactions of few ( N ) electrons confined in a disk shaped quantum dot, with a large magnetic field B=B^* applied in the z-direction (orthogonal to the dot), produce a fully spin polarized ground state. We numerically study the splitting of the levels corresponding to the multiplet of total spin S=N/2 (each labeled by a different total angular momentum J_z ) in presence of an electric field parallel to B , coupled to S by a Rashba term. We find that the first excited state is a spin
... xciton with a reversed spin at the origin. This is reminiscent of the Quantum Hall Ferromagnet at filling one which has the skyrmion-like state as its first excited state. The spin exciton level can be tuned with the electric field and infrared radiation can provide energy and angular momentum to excite it.