Mechanisms and Opportunities for Tunable High-Purity Single Photon Emitters: A Review of Hybrid Perovskites and Prospects for Bright Squeezed Vacuum

TL;DR

This review analyzes mechanisms and prospects for high-purity, tunable single-photon emitters, focusing on hybrid perovskites and bright squeezed vacuum, to advance scalable quantum photonic technologies.

Contribution

It introduces a physics-based classification of SPEs, evaluates hybrid perovskite quantum dots, and explores bright squeezed vacuum as a novel photon source.

Findings

Hybrid perovskite quantum dots offer tunable, narrow linewidth emission at room temperature.

The performance framework guides scalable SPE development beyond current limitations.

Bright squeezed vacuum states could enable multiplexable, high-purity photon generation.

Abstract

Single-photon emitters (SPEs) are central to quantum communication, computing, and metrology, yet their development remains constrained by trade-offs in purity, indistinguishability, and tunability. This review presents a mechanism-based classification of SPEs, offering a physics-oriented framework to clarify the performance limitations of conventional sources, including quantum emitters and nonlinear optical processes. Particular attention is given to hybrid organic-inorganic perovskite quantum dots (HOIP QDs), which provide size- and composition-tunable emission with narrow linewidths and room-temperature operation. Through comparative analysis of physical mechanisms and performance metrics, we show how HOIP QDs may address key limitations of established SPE platforms. Recognizing the constraints of current deterministic sources, we introduce a performance framework to guide the development of scalable SPEs, and examine the theoretical potential of bright squeezed vacuum (BSV) states, discussing how BSV mechanisms could serve as a promising avenue for multiplexable, high-purity photon generation beyond conventional heralded schemes. The review concludes by outlining future directions for integrating HOIP- and BSV-based concepts into scalable quantum photonic architectures.