Maharjan Nikesh, Nakarmi Mim Lal
Department of Physics, Brooklyn College and the Graduate Center of the City University of New York, Brooklyn, NY 11210 USA.
MRS Adv. 2021;6(11):307-310. doi: 10.1557/s43580-021-00059-4. Epub 2021 May 12.
Deep ultraviolet (UV) photoluminescence (PL) spectroscopy was employed to study the luminescence properties of hexagonal boron nitride (h-BN) crystal powders after annealing the samples at different temperatures in the range of 100-900 °C for 1 h in ambient air. The PL spectrum from the h-BN powder samples annealed around 700 °C showed strong luminescence intensity at 5.49 eV along with enhanced phonon-assisted band-edge emission at 5.90 eV. Additionally, it revealed sharp atomic-like emission lines in UV region at 4.10, 4.12, 4.14, and 4.16 eV with line widths less than 1 nm from the annealed samples which were not present in the unannealed samples. Power- and temperature-dependent PL measurements of the sharp atomic-like emission lines exhibited robust nature of the energy peak positions. Based on the theoretical reports, the sharp emission lines could be carbon-related defects.
采用深紫外（UV）光致发光（PL）光谱研究了六方氮化硼（h-BN）晶体粉末在100-900°C范围内不同温度下于环境空气中退火1小时后的发光特性。在700°C左右退火的h-BN粉末样品的PL光谱在5.49 eV处显示出很强的发光强度，同时在5.90 eV处声子辅助带边发射增强。此外，从退火样品中还发现了在紫外区域4.10、4.12、4.14和4.16 eV处有尖锐的类原子发射线，线宽小于1 nm，而未退火样品中不存在这些发射线。对尖锐类原子发射线进行的功率和温度相关的PL测量表明能量峰值位置具有稳健性。基于理论报道，这些尖锐发射线可能与碳相关缺陷有关。
