Photonic crystal (PhC) nanocavities, which offer ultimate light confinement in both time and space, play an indispensable role in enhancing light-matter interactions. They provide an effective pathway to study solid-state quantum photonics with embedded quantum dots (QDs). However, during the nanocavity design, the balance between the QD and cavity performance is rarely considered. Here, we propose an $\mathrm{H}0/1$ photonic crystal cavity by introducing an additional air hole at the center of an H0-type cavity. Using automated optimization based on the covariance matrix adaptation evolution strategy, the cavity simultaneously achieves a high quality factor $Q$ of approximately ${10}^6$ and a small mode volume ($V$) of $0.317(\lambda /n{)}^3$, while preserving a sufficiently large effective dielectric area that is essential to achieve high spatial field-QD overlap and maintain the exciton coherence of the QD theoretically. The Purcell enhancement of a single QD in the $\mathrm{H}0/1$ cavity is realized experimentally. Compared with cavities possessing a single field maximum, the high-$Q$ low-$V$ $\mathrm{H}0/1$ cavity mode supports two spatially separated field maxima. It enables cavity-mediated collective interactions between distinct QDs when taking full advantage of the extremely strong light confinement capability. The potential of the proposed design for studying superradiance and subradiance is further discussed, offering a platform for quantum information applications.

Close

PrevNext

View figure in article

• Light-matter interaction
• Photonic crystals
• Quantum optics
• Optical microcavities
• Quantum dots
• Semiconductor microcavities
• Photoluminescence