Enhanced room-temperature quantum-dot effects in modulation-doped InAs/GaAs quantum dots

Abstract

Modulation-doped InAs/GaAs quantum dots (QDs) show bright photoluminescence (PL) at 300 K, linear increase of PL intensity on excitation at 300 K and rather temperature insensitive PL intensity and carrier lifetime, in contrast to undoped QDs. Systematic analyses indicate that those advantageous behaviors come from the enhanced Coulomb attraction due to excess carriers in doped QDs. The stronger Coulomb interaction increases the thermal activation energy, keeps more carriers in QDs, and provides enhanced QD characteristics at room temperature.