Thermal behaviors of the sharp zero–phonon luminescence lines of NV center in diamond

Abstract

The nitrogen–vacancy (NV) center in diamond has quickly emerged as a promising solid–state candidate for single-photon emitters, quantum bits or qubits, and ultrasensitive sensors in recent years. At the same time, it may also provide an excellent molecule–like platform for exploiting the fundamental principles of quantum mechanics, such as quantum entanglement mechanism. Therefore, it is of both scientific and technological significance to have an in-depth investigation on NV center, especially on the optoelectronic processes and optical properties of NV center. In this study, the temperature dependence of the sharp zero–phonon lines (ZPL) of luminescence of NV center with neutral and negative charge states in a CVD–grown diamond crystal is measured in the range from 5 K to 300 K. It is shown that the experimental data, including the temperature induced broadening, peak shift and even intensity quenching of the two sharp ZPL lines of NV0 and NV−1, all on the whole support a generalized quantum theory in spite of in which Franck–Condon, harmonic and Debye approximations were assumed. In particular, the thermal quenching tendency of the integrated intensities can be described by Debye–Waller factor in the theory of the Mössbauer effect. The study sheds some light on the challenging issue, the temperature dependence of the so–called zero-phonon luminescence of NV center in diamond.