6533b824fe1ef96bd1280bde

RESEARCH PRODUCT

Ultrafast sequential charge transfer in a double quantum dot

Esa RäsänenA. Putaja

subject

PhysicsQuantum PhysicsField (physics)Condensed Matter - Mesoscale and Nanoscale PhysicsFOS: Physical sciencesCharge (physics)Condensed Matter PhysicsOptimal controlElementary chargeElectronic Optical and Magnetic MaterialsQuantum dotQuantum mechanicsExcited stateElectric fieldMesoscale and Nanoscale Physics (cond-mat.mes-hall)Quantum Physics (quant-ph)Ultrashort pulse

description

We use optimal control theory to construct external electric fields which coherently transfer the electronic charge in a double quantum-dot system. Without truncation of the eigenstates we operate on desired superpositions of the states in order to prepare the system to a localized state and to coherently transfer the charge from one well to another. Within a fixed time interval, the optimal processes are shown to occur through several excited states. The obtained yields are generally between 99% and 99.99% depending on the field constraints, and they are not dramatically affected by strict frequency filters which make the fields (e.g., laser pulses) closer to experimental realism. Finally we demonstrate that our scheme provides simple access to hundreds of sequential processes in charge localization while preserving the high fidelity.

https://dx.doi.org/10.48550/arxiv.1006.5615