Fast and robust exciton preparation in a coupled semiconductor quantum dot-metal nanoparticle system using shortcuts to adiabaticity

We study the efficient preparation of the exciton state in a hybrid nanostructure composed by a semiconductor quantum dot and a metallic nanoparticle, when starting from the ground state, using pulses derived with the method of shortcuts to adiabaticity. We show with numerical simulations that high levels of exciton population can be obtained for a wide range of interparticle distances and for short pulse durations. This behavior appears also to be robust against small positioning errors of the system. The fidelity of the population inversion degrades for smaller distances and longer pulses, as the nonlinear terms in the equations, expressing the quantum dot-metal nanoparticle interaction, become stronger and affect the evolution for longer times. The present work is expected to help schemes toward the generation of single photons on demand or ultrafast nanoswitches, where the controlled population inversion in semiconductor quantum dots coupled to metal nanoparticles is an important task.

Automated summary

Efficient preparation of the exciton state in a hybrid nanostructure composed of a semiconductor quantum dot and a metallic nanoparticle can be achieved using pulses derived with the method of shortcuts to adiabaticity. The population inversion fidelity degrades for smaller distances and longer pulse durations due to the stronger nonlinear terms in the interaction equations. This study is expected to contribute to the development of schemes for generating single photons on demand or ultrafast nanoswitches.