Low- to Room-Temperature Studies of Silicon Nitride Single Photon Emitters

We recently developed a method for generating intrinsic single-photon emitters in silicon nitride (SiN) by thermal annealing of low autofluorescence SiN films. We found that the intrinsic emitters in SiN are bright, stable, linearly polarized, and exhibit high single-photon purity at room temperature [1]. Also, we demonstrated the first realization of SiN waveguides with intrinsic quantum emitters and coupling of single-photon emission into the waveguide mode [2]. The exact atomic structure and energy levels of these emitters is yet to be fully understood. In this work, we study optical transition wavelengths, linewidths, and single-photon properties of these emitters as a function of temperature from 4K to 300K. We found the emergence of narrow emission lines at cryogenic temperatures, which have a linewidth of ~1 meV at 4.2 K. Furthermore, the intensity, linewidth, and wavelength of these peaks all show clear temperature dependence. The combination of temperature- and time-resolved measurements allows us to study the homogeneous and inhomogeneous broadening of emission. We will report on our study of the fundamental properties of single-photon emitters in SiN, which are critical for potential quantum photonic applications.

[1] A. Senichev et al, Sci. Adv. 7.50 (2021)

[2] A. Senichev et al, ACS Phot. 9.10 (2022): 3357-3365