Hole burning on the time-resolved optically detected ESR spectra of self-trapped excitons in alkali halides

Abstract

The homogeneous and inhomogeneous line widths of the ESR spectra of self-trapped excitons (STEs) in KBr have been investigated using the methods of time-resolved optically detected magnetic resonance (ODMR) and hole burning. The line shape of each partially resolved hyperfine line is the Gaussian function whose width is between 13 and 15 mT (FWHM). The homogeneous line width is estimated to be ⩽0.2 mT from the microwave power dependence of the ODMR signal intensity. In contrast, from the hole-burning experiment, we acquired knowledge of the broad hole whose shape is the same as that of the single hyperfine line. We suppose that an initially narrow burned hole becomes broad within a shorter period less than millisecond by so-called spectral diffusion.