The temperature and pressure dependences of the Raman spectrum of the transverse-optical mode of cubic boron nitride were calibrated for applications to a Raman spectroscopy pressure sensor in optical cells to about 800 K and 90 GPa. A significant deviation from linearity of the pressure dependence is confirmed at pressures above 20 GPa. At ambient temperature, dv/dP slopes are 3.41(7) and 2.04(7) cm-1/GPa at 0 and 90 GPa, respectively. A polynomial expression is used to fit the pressure-temperature dependence of the Raman line. The pressure dependence does not significantly change with temperature, as determined from experiments conducted up to 800 K. At 0 GPa, the dv/dP slope is 3.46(7) cm-1/GPa at 800 K. At pressures above 90 GPa, the Raman spectrum of the transverse-optical mode cannot be observed because of an overlap of the signals of cubic boron nitride and diamond used as the anvils in the high-pressure cell.
Ono, S., Mibe, K., Hirao, N., & Ohishi, Y. (2015). In situ Raman spectroscopy of cubic boron nitride to 90 GPa and 800 K. Journal of Physics and Chemistry of Solids, 76, 120–124. https://doi.org/10.1016/j.jpcs.2014.09.001