Multi-harmonic Quantum Dot Optomechanics in fused LiNbO3-(Al)GaAs hybrids

Emeline D. S. Nysten, Yong Heng Huo, Hailong Yu, Guo Feng Song, Armando Rastelli, Hubert J. Krenner

Journal of Physics D: Applied Physics 50 43LT01 (2017) DOI: J. Phys. D: Appl. Phys.

We fabricated an acousto-optic semiconductor hybrid device for strong optomechanical coupling of individual quantum emitters and a surface acoustic wave. Our device comprises of a surface acoustic wave chip made from highly piezoelectric LiNbO3 and a GaAs-based semiconductor membrane with an embedded layer of quantum dots. Employing multi- harmonic transducers, we generated sound waves on LiNbO3 over a wide range of radio frequencies. We monitored their coupling to and propagation across the semiconductor membrane, both in the electrical and optical domain. We demonstrate the enhanced optomechanical tuning of the embedded quantum dots with increasing frequencies. This effect was veri ed by nite element modelling of our device geometry and attributed to an increased localization of the acoustic eld within the semiconductor membrane. For moderately high acoustic frequencies, our simulations predict strong optomechanical coupling, making our hybrid device ideally suited for applications in semiconductor based quantum acoustics.