[25p-E204-1~17] 6.2 Carbon-based thin films

▲ [25p-E204-4] Study of transition process of NV charge state in diamond Schottky barrier diode by transient photocurrent and photocapacitance

〇Junjie Guo^1,2, Aboulaye Traore¹, Toshiharu Makino^1,2, Masahiko Ogura², Muhammad Hafiz Bin Abu Bakar^1,2, Etienne Gheeraert^1,4, Satoshi Yamasaki^2,3,1, Takeaki Sakurai¹ (1.Tsukuba Univ., 2.AIST, 3.Kanazawa Univ., 4.Univ. Grenoble Alpes)

Keywords:diamond Schottky barrier diode, NV center, transient photocurrent

In recent years, the research of nitrogen-vacancy (NV) centers in diamond have attracted wide attention due to its potential applications in the quantum field. The sensitive methods for NV detection in diamond devices are also necessary and important. Here, we use transient photocurrent and photocapacitance to explore the transition process of the NV center in the diamond Schottky barrier diode, identify the current and capacitance changes caused by NV photoionization. Through exploration of the transient photocurrent under different light intensities at 700nm and 500nm, it is found that there is a photocurrent overshoot under the light of 700nm, and this phenomenon disappears at 500nm light. It is believed that the overshoot is due to the redistribution of the internal electric field caused by the rapid accumulation of electrons in the depletion layer. It is different under 500nm green light with high-energy photons. The change in the number of electrons in the depletion layer is not significant due to the switching between different charge states of NV centers by a two-photon process and will not cause a rapid redistribution of the internal electric field, so the photocurrent overshoot phenomenon disappears. Therefore, we demonstrated the photoionization of NV centers induced a change in SBDs current and capacitance, which provides us with ideas for a better and new spin detection technique.