Optical Properties of Atomic Defects in Hexagonal Boron Nitride Flakes under High Pressure

We investigate the pressure spectral characteristics and the effective tuning of defect emissions in hexagonal boron nitride (hBN) at low temperatures using a diamond anvil cell (DAC). It is found that the redshift rate of emission energy is up to 10 meV/GPa, demonstrating a controllable tuning of single photon emitters through pressure. Based on the distribution character of pressure coefficients as a function of wavelength, different kinds of atomic defect states should be responsible for the observed defect emissions.