Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2, Czech Republic.
Opt Lett. 2010 Feb 15;35(4):577-9. doi: 10.1364/OL.35.000577.
We have observed what we believe to be a new phenomenon in nanocrystalline diamond membranes. The optical thickness of the membrane is changed under laser irradiation, which leads to a spectral shift of interference fringes in the transmission and photoluminescence spectra of high-quality thin self-supporting nanocrystalline membranes. The direction of the spectral shift (red/blue) can be tuned by the ambient air pressure. The effect is reversible and is accompanied by changes in photoluminescence intensity. We interpret the results in terms of the changes in the index of refraction caused by the photoinduced adsorption/desorption of air molecules that subsequently affect the properties of subgap energy states related to the surface and the grain boundaries of the nanocrystals.
我们在纳米金刚石膜中观察到一种新现象。在激光辐照下，膜的光学厚度发生变化，导致高质量的自支撑纳米晶膜的透射和光致发光光谱中的干涉条纹发生光谱位移。光谱位移的方向（红移/蓝移）可以通过环境气压来调节。这种效应是可逆的，并伴随着光致发光强度的变化。我们根据光诱导吸附/解吸空气分子引起的折射率变化来解释结果，这些空气分子随后会影响与纳米晶的表面和晶界有关的能隙下的能量状态的性质。
