Defect-related photoluminescence of hexagonal boron nitride

Physical review. B, Condensed matter (Impact Factor: 3.66). 11/2008; DOI: 10.1103/PhysRevB.78.155204
Source: arXiv

ABSTRACT Photoluminescence of polycrystalline hexagonal boron nitride (hBN) was measured by means of time- and energy-resolved spectroscopy methods. The observed bands are related to DAP transitions, impurities and structural defects. The excitation of samples by high-energy photons above 5.4 eV enables a phenomenon of photostimulated luminescence (PSL), which is due to distantly trapped CB electrons and VB holes. These trapped charges are metastable and their reexcitation with low-energy photons results in anti-Stockes photoluminescence. The comparison of photoluminescence excitation spectra and PSL excitation spectra allows band analysis that supports the hypothesis of Frenkel-like exciton in hBN with a large binding energy.

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