Low‐temperature excitons produced by two‐photon excitation in high‐purity diamond crystals
Low‐temperature excitons produced by two‐photon excitation in high‐purity diamond crystals
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高纯金刚石晶体中双光子激发产生的低温激子
DOI：
10.1002/pssb.200879877
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
M. Kuwata
中科院分区：
文献类型：
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作者：
N. Naka;T. Kitamura;J. Omachi;M. Kuwata
我们已经观察到由于自由激子和金刚石中的电子-空穴液滴的边缘发射，通过使用257 nm的亚皮秒激光脉冲的双光子激发。我们发现双光子激发下的激子温度比单光子激发的情况低得多。通过光谱分析提取了3.4 K的最低激子温度。为了理解双光子和单光子激发下激子温度的差异，我们讨论了一种加热机制，该机制取决于晶体中电子空穴对沿着激光束的密度分布。（© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA，魏因海姆）
We have observed edge emission due to free excitons and electron–hole droplets in diamond by two‐photon excitation using subpicosecond laser pulses at 257 nm. We find that excitonic temperatures under two‐photon excitation are much lower than the case of one‐photon excitation. A minimum excitonic temperature of 3.4 K is extracted by spectral analysis. In order to understand the difference of the excitonic temperatures under two‐photon and one‐photon excitations, we discuss a heating mechanism which depends on the density distribution of the electron–hole pairs in the crystal along the laser beam. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)