Engineering of Solid-State Single-Photon Sources Based on Perovskite Quantum Dots in Perovskite Matrix

Semiconductor quantum dots (QD) have emerged to be one of the promising candidates for on-demand single-photon emitters (SPE), which are one of the key units in quantum photonic circuits and quantum information processing. However, despite wide investigation of colloidal QDs, implantation of such SPE system in solid states for electrical excitation is less developed. Here, we have demonstrated the first solution-processed perovskite-based single-photon source in a solid-state medium, by embedding perovskite emission centers into a wide-bandgap perovskite matrix. Such ‘dot-in-a-matrix’ system exhibits a clear photon-antibunching signature, with second-order correlation function (g2(0)) to be ~0.1 at cryogenic temperatures. The photoluminescence (PL) spectrum exhibits narrow emissions lines at 1.8-1.9eV with 2-3meV FWHM at T=6K, indicating high crystallinity of the localized emission centers. High-resolution transmission electron microscope (HR-TEM) confirms the presence of nanometer-sized domains, which indicates the formation of quantum dots during the rapid crystallization of the precursor solvent. Monitoring PL with time suggests blinking-free emission and spectral diffusion of <1meV. PL spectra exhibits a linear dependence with excitation intensity, indicating the mono-recombination dominated by single exciton rather than bi-exciton or charged exciton states. Additionally, exciton fine structures have been detected, which are likely due to the anisotropic structures of individual emitters. Finally, we have demonstrated the capability of electrical luminescence by sandwiching the matrix between electron-transport and hot-transport layers. Such demonstration may pave the pathway of on-chip integration of single-photon sources for quantum optical systems.