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Indirect Optical Absorption of Single Crystalline beta-FeSi2

Haruhiko Udono·Isao Kikuma·Tsuyoshi Okuno·Yasuaki Masumoto·Hiroyuki Tajima
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Abstract

We investigated optical absorption spectra near the fundamental absorption edge of beta-FeSi2 single crystals by transmission measurements. The phonon structure corresponding to the emission and absorption component was clearly observed in the low-temperature absorption spectra. Assuming exciton state in the indirect allowed transition, we determined a phonon energy of 0.031 +- 0.004 eV. A value of 0.814 eV was obtained for the exciton transition energy at 4K.

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Haruhiko Udono, Isao Kikuma, Tsuyoshi Okuno, Yasuaki Masumoto, Hiroyuki Tajima. 2004-05-20. Indirect Optical Absorption of Single Crystalline beta-FeSi2. https://doi.org/10.1063/1.1790590

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