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physica status solidi (b)

Low‐temperature excitons produced by two‐photon excitation in high‐purity diamond crystals

N. Naka, T. Kitamura, Junko Omachi, Makoto Kuwata‐Gonokami

Published Oct 20, 2008• 23 citations
Publisher

Abstract

Abstract 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)

DOI
10.1002/pssb.200879877

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