Creation of supercooled exciton gas and transformation to electron-hole droplets in diamond
Creation of supercooled exciton gas and transformation to electron-hole droplets in diamond
复制标题
金刚石中过冷激子气体的产生和电子空穴液滴的转变
DOI：
10.1103/physrevb.68.081202
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发表时间：
2003
影响因子：
3.7
通讯作者：
M. Kuwata
中科院分区：
文献类型：
--
作者：
M. Nagai;R. Shimano;K. Horiuchi;M. Kuwata
利用时间分辨发射光谱研究了高纯度单晶金刚石在带隙附近光激发下电子空穴液滴的形成动力学。在激子莫特跃迁密度以下，光生载流子被冷却，在30 ps内出现激子发射。液滴的宽发射带缓慢上升，伴随着激子发射强度在接下来的100皮秒内降低。这一光谱变化表明低温过饱和激子气体的初始形成和随后密集激子气体的空间凝聚成电子空穴液滴。
We investigated the formation dynamics of electron-hole droplets in a high-purity single crystal diamoad under photoexcitation near the band gap using time-resolved emission spectroscopy. Below the exciton Mott transitiondensity, photogenerated carriers are cooled, and exciton emission appears within 30 ps. A broad emission band of droplets rises slowly, accompanied with a reduction in the exciton emissico intensity in the next hundred picoseconds. This spectral change indicates the initial formation of low-temperature supersaturated exciton gas and subsequent spatial condensation of dense exciton gas into electron-hole droplets.