Optical Phonon Lasing in Semiconductor Double Quantum Dots

TL;DR

This paper proposes a novel scheme for optical phonon lasing in semiconductor double quantum dots, demonstrating conditions for lasing and antibunching, and exploring effects of electron-phonon coupling.

Contribution

It introduces the concept of optical phonon lasing in DQDs and analyzes the effects of electron-phonon interactions on phonon emission properties.

Findings

Lasing occurs when DQD is pumped at high tunneling rates.

Antibunching of phonon emission observed at slow tunneling.

Strong electron-phonon coupling leads to thermalization effects.

Abstract

We propose optical phonon lasing for a double quantum dot (DQD) fabricated in a semiconductor substrate. We show that the DQD is weakly coupled to only two LO phonon modes that act as a natural cavity. The lasing occurs for pumping the DQD via electronic tunneling at rates much higher than the phonon decay rate, whereas an antibunching of phonon emission is observed in the opposite regime of slow tunneling. Both effects disappear with an effective thermalization induced by the Franck-Condon effect in a DQD fabricated in a carbon nanotube with a strong electron-phonon coupling.