In situ tuning biexciton antibinding-binding transition and fine-structure splitting through hydrostatic pressure in single InGaAs quantum dots

¹ State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences - Beijing, 100083, PRC
² Key Laboratory of Quantum Information, University of Science and Technology of China Hefei, 230026, PRC

Received: 21 April 2014
Accepted: 4 July 2014

Abstract

Exciton and biexciton emission energies as well as excitonic fine-structure splitting (FSS) in single (In,Ga)As/GaAs quantum dots (QDs) have been continuously tuned using hydrostatic pressure up to 4.4 GPa. The blue shift of excitonic emission and the increase of FSS are 320 meV and , respectively, which are significantly greater than those that could be achieved by previously reported techniques. We successfully produce a biexciton antibinding-binding transition along with a detailed polarization-resolved emission spectra. It is shown that the biexciton binding energy linearly increases with increasing pressure and tends to be sublinear at high pressure. We have performed atomistic pseudopotential calculations on realistic QDs to understand the pressure-induced effects.