In this letter, the high-order harmonic generation (HHG) of wurtzitic and hexagonal boron nitride (h-BN) under ultrafast intense laser field was studied by solving an extended multiband semiconductor Bloch equations (SBEs). The results showed that for both the wurtzitic and hexagonal structures, the cutoff energy of the HHG was extended linearly by increasing the field strength, and the efficiency was suppressed as the wavelength of laser increased. It was worth noting that for hexagonal structure, the efficiency of HHG was 1–2 orders of magnitude higher than that of the wurtzitic structure. At the same time, the hexagonal structure significantly improved the cutoff energy of HHG from BN.

在这封信中，通过求解扩展的多带半导体布洛赫方程 (SBE)，研究了纤锌矿和六方氮化硼 ( h- BN) 在超快强激光场下的高次谐波产生 (HHG )。结果表明，对于纤锌矿和六方结构，HHG 的截止能量通过增加场强线性扩展，并且效率随着激光波长的增加而受到抑制。值得注意的是，对于六方结构，HHG 的效率比纤锌矿结构高 1-2 个数量级。同时，六方结构显着提高了 BN 的 HHG 的截止能。