Stable Single Photon Emitters with Large Debye–Waller Factor in Silica

Single color centers in wide bandgap materials show great potential for various quantum applications. However, most of the well-known single color centers are in diamond and silicon carbide, which are difficult to use for fabricating photonic structures. Thus, it is essential to find new single defects in materials that are compatible with well-established, industrial-scale nano- or microfabrication of photonic structures. Here, we report a method to generate stable single-photon emitters in silica. The spectra of these single-photon emitters show a strong zero-phonon line, and the Debye–Waller factors (F_DW) were measured up to 0.74. The power-dependent photon autocorrelation results demonstrate a strong bunching effect at high excitation power, and the results can be described by a standard three-level system model. The photoluminescence (PL) emission polarization, saturation intensity, and stability of these single-photon emitters are also investigated.