Electric field influence on exciton absorption of Er doped and undoped InSe single crystals


Guerbulak B., Kundakci M., Ates A., Yildirim M.

Physica Scripta, cilt.75, sa.4, ss.424-430, 2007 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 75 Sayı: 4
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1088/0031-8949/75/4/008
  • Dergi Adı: Physica Scripta
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.424-430
  • Atatürk Üniversitesi Adresli: Evet

Özet

Undoped InSe and Er doped InSe (InSe:Er) single crystals were grown by using the Stockbarger method. Ingots had no cracks and voids on the surface. The absorption measurements were carried out in InSe and InSe:Er samples for U≤0 and U≤30 V in the temperature range 10-320 K with a step of 10 K. Electric field effects on excitons are observed in InSe and InSe:Er single crystals. The absorption edge shifted towards longer wavelengths and decreased intensity in absorption spectra under an electric field E≅5.9 kV cm-1. The applied electric field caused a shifting and a decreasing of intensity in the absorption spectra. The shifting of the absorption edge can be explained on the basis of the Franz-Keldysh effect (FKE) or thermal heating of the sample under the electric field. At 10 and 320 K, the first exciton energies for InSe were calculated as 1.336 and 1.291 eV for zero voltage and 1.331 and 1.280 eV for electric field and InSe:Er as 1.329 and 1.251 eV for zero voltage and 1.318 and 1.248 eV for electric field, respectively. © 2007 The Royal Swedish Academy of Sciences.