0 M ay 2 00 4 Indirect Optical Absorption of Single Crystalline β - FeSi
نویسندگان
چکیده
We investigated optical absorption spectra near the fundamental absorption edge of β-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. ∗Electronic address: [email protected]
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