Defect-induced single-photon emission in ZnPS3

We investigated single photon emitters in ZnPS3 bulk crystal. The available data include measurements of sample using photoluminescence (PL), Raman scattering (RS), atomic force microscopy (AFM), time-resolved PL, polarization-resolved PL techniques. The sample was investigated at 5 K temperature. The PL experiments were performed using λ = 632.8 nm excitation from the continuous-wave (CW) helium-neon laser. Measurements were carried out in a dry cryogenic system with a base temperature of 5 K. The sample was mounted onto the x-y-z piezo stages for precise positioning. The measurements were conducted in a back-scattering geometry, with laser focusing and collection carried out using a cold objective with a numerical aperture of 0.82. For the detection of the signal, the light was dispersed by a SpectraPro HRS-750 spectrometer and detected by a PyLoN 100-BRX LN2 cooled charge-coupled device (CCD) camera (both Princeton Instruments). For the photoluminescence excitation measurements, a broadband super-continuum laser coupled to the tunable bandpass filter has been used (SuperK Extreme, NKT Photonics). The RS experiments were performed using λ = 515 nm excitation from the CW laser diode. The studied sample was placed on a cold finger in a continuous-flow cryostat mounted on x–y motorized positioners. The measurements were conducted in a back-scattering geometry, with laser focusing and collection carried out using a 50x long-working-distance objective with a numerical aperture of 0.55. For the detection of the signal, the light was dispersed by a SpectraPro HRS-750 spectrometer and detected by a PyLoN 100-BRX LN2 cooled CCD camera (both Princeton Instruments).Time-resolved PL measurements have been performed by using a single photon counter (Excelitas SPCM-AQRH-16-BR1) triggered by laser pulses. For excitation, a broadband super-continuum laser coupled to the tunable bandpass filter has been used (SuperK Extreme, NKT Photonics). The correlation function measurements have been conducted in the Hanbury Brown and Twiss geometry. The signal from two single photon counters has been correlated with the PicoHarp 300 module. After normalization, the recorded histograms are equivalent to the normalized second-order correlation functionTopography measurements were performed using a Bruker Dimension FastScan XR atomic force microscope operated in tapping mode with RTESPA-150 cantilevers.