Quantum control of coupled two-electron dynamics in quantum dots.

Research paper by R R Nepstad, L L Sælen, I I Degani, J P JP Hansen

Indexed on: 27 May '09Published on: 27 May '09Published in: Journal of physics. Condensed matter : an Institute of Physics journal


We investigate optimal control strategies for state to state transitions in a model of a quantum dot molecule containing two active strongly interacting electrons. The Schrödinger equation is solved nonperturbatively in conjunction with several quantum control strategies. This results in optimized electric pulses in the terahertz regime which can populate combinations of states with very short transition times. The speed-up compared to intuitively constructed pulses is an order of magnitude. We furthermore make use of optimized pulse control in the simulation of an experimental preparation of the molecular quantum dot system. It is shown that exclusive population of certain excited states leads to a complete suppression of spin dephasing, as was indicated in Nepstad et al (2008 Phys. Rev. B 77 125315).