The question of optical bandgap anisotropy in the monoclinic semiconductor beta-Ga2O3 was revisited by combining accurate optical absorption measurements with theoretical analysis, performed using different advanced computation methods. As expected, the bandgap edge of bulk beta-Ga2O3 was found to be a function of light polarization and crystal orientation, with the lowest onset occurring at polarization in the ac crystal plane around 4.5–4.6 eV; polarization along b unambiguously shifts the onset up by 0.2 eV. The theoretical analysis clearly indicates that the shift in the b onset is due to a suppression of the transition matrix elements of the three top valence bands at G point.

Theoretical and experimental investigation of optical absorption anisotropy in β-Ga2O3 / Ricci, F; Boschi, Francesco; Baraldi, Andrea; Filippetti, A; Higashiwaki, M; Kuramata, A; Fiorentini, V; Fornari, Roberto. - In: JOURNAL OF PHYSICS. CONDENSED MATTER. - ISSN 0953-8984. - 28:22(2016), p. 224005. [10.1088/0953-8984/28/22/224005]

Theoretical and experimental investigation of optical absorption anisotropy in β-Ga2O3

BOSCHI, Francesco;BARALDI, Andrea;FORNARI, Roberto
2016-01-01

Abstract

The question of optical bandgap anisotropy in the monoclinic semiconductor beta-Ga2O3 was revisited by combining accurate optical absorption measurements with theoretical analysis, performed using different advanced computation methods. As expected, the bandgap edge of bulk beta-Ga2O3 was found to be a function of light polarization and crystal orientation, with the lowest onset occurring at polarization in the ac crystal plane around 4.5–4.6 eV; polarization along b unambiguously shifts the onset up by 0.2 eV. The theoretical analysis clearly indicates that the shift in the b onset is due to a suppression of the transition matrix elements of the three top valence bands at G point.
2016
Theoretical and experimental investigation of optical absorption anisotropy in β-Ga2O3 / Ricci, F; Boschi, Francesco; Baraldi, Andrea; Filippetti, A; Higashiwaki, M; Kuramata, A; Fiorentini, V; Fornari, Roberto. - In: JOURNAL OF PHYSICS. CONDENSED MATTER. - ISSN 0953-8984. - 28:22(2016), p. 224005. [10.1088/0953-8984/28/22/224005]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11381/2805680
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 82
  • ???jsp.display-item.citation.isi??? 75
social impact