Dynamic Control of the Coupling between Dark and Bright Excitons with Vibrational Strain

Abstract

We numerically and experimentally investigate strain-induced coupling between dark and bright excitons and its dynamic control using a gallium arsenide (GaAs) micromechanical resonator. Uniaxial strain induced by the mechanical resonance efficiently detunes the exciton energies and modulates the coupling strength via the deformation potential in GaAs. This allows optical access to the long-lived dark states without using any external electromagnetic field. This field-free approach could be expanded to a wide range of solid-state materials, leading to on-chip excitonic memories and circuits based on micromechanical resonators.

Dark-bright exciton coupling in asymmetric quantum dots

“…(5). Moreover, this γ parameter can potentially be tuned by applying strain [28,36] in the same way that the BE FSS was tuned by piezoelectric-induced anisotropic strain [37]. We also note that the | ±1 with | ∓2 coupling 12 is a second-order term in VBM and should be weaker.…”

Optomechanics of Chiral Dielectric Metasurfaces

“…The main peculiarity of our device resides instead in the use of a chiral pattern, with the consequent possibility to enable polarization‐dependent optomechanical effects; moreover, as highlighted above, the choice of a dielectric material (GaAs) allows for almost lossless operation. GaAs has also other advantages: it is easily machinable, it can host active elements, and it has strong nonlinear optical response . Furthermore, being its refractive index similar to that of silicon, the design presented here can be straightforwardly exported to complementary metal‐oxide‐semiconductor (CMOS)‐compatible platforms for eventual integrability with electronics.…”

Полупроводниковые Гетероструктуры Первого Рода С Непрямой Запрещенной Зоной На Подложках С Ориентацией (110)

“…Неоднородность спиновой населенности можно создавать с помощью оптической ориентации -за счет возбуждения циркулярно поляризованным светом. Это -хорошо отработанная и активно применяемая методика при изучении спиновой динамики экситонов и трионов в прямозонных полупроводниках, КЯ и КТ [36,37]. Из-за слабости экситон-фотонного взаимодействия оптическая ориентация неприменима для возбуждения спиновой подсистемы непрямозонных структур.…”