Recent progress in room-temperature single-photon emission in quantum dots: the role of chirality and surface...

Single-photon emission (SPE) is an indispensable component of emerging quantum technologies, including quantum communication, computation, and sensing. While cryogenic platforms have demonstrated near-ideal SPE, their reliance on low-temperature operation limits scalability and practical deployment. This review focuses on recent progress toward efficient and stable room-temperature single-photon sources (RT-SPSs), with particular emphasis on semiconductor colloidal quantum dots (QDs) and metal-halide perovskite quantum dot (PQD) emitters based on key performance metrics such as photon purity, brightness, emission linewidth, and photostability. Special attention is given to emerging strategies that overcome room-temperature limitations, including surface and ligand engineering, defect control, and integration with advanced nanophotonic architectures. In particular, the role of chirality in QDs is highlighted as a powerful symmetry-breaking mechanism that enables polarization-selective emission, excitonic state control, and spin-dependent processes. Furthermore, coupling quantum emitters to plasmonic cavities, bound states in the continuum, and metasurfaces is discussed as an effective route to enhance light-matter interactions and access coherent regimes at ambient conditions. By consolidating recent experimental and theoretical advances, this review outlines key challenges, emerging solutions, and future directions toward scalable, RT-SPSs compatible with integrated quantum photonic platforms.