Intermediate band to conduction band optical absorption in ZnTeO


Autoria(s): Antolín Fernández, Elisa; Chen, C.; Ramiro Gonzalez, Iñigo; Foley, James; López Estrada, Esther; Artacho Huertas, Irene; Hwang, J.; Teran, A.; Hernández Martín, Estela; Tablero Crespo, César; Martí Vega, Antonio; Phillips, J.D.; Luque López, Antonio
Data(s)

2014

Resumo

ZnTe doped with high concentrations of oxygen has been proposed in previous works as an intermediate band (IB) material for photovoltaic applications. The existence of extra optical transitions related to the presence of an IB has already been demonstrated in this material and it has been possible to measure the absorption coefficient of the transitions from the valence band (VB) to the IB. In this study, we present the first measurement of the absorption coefficient associated with transitions from the IB to the conduction band (CB) in ZnTeO. The samples used are 4-mum-thick ZnTe layers with or without O in a concentration ~10 19 cm -3, which have been grown on semiinsulating GaAs substrates by molecular beam epitaxy (MBE). The IB-CB absorption coefficient peaks for photon energies ~0.4 eV. It is extracted from reflectance and transmittance spectra measured using Fourier transform infrared (FTIR) spectroscopy. Under typical FTIR measurement conditions (low light intensity, broadband spectrum), the absorption coefficient in IB-to-CB transitions reaches 700 cm -1. This is much weaker than the one observed for VB-IB absorption. This result is consistent with the fact that the IB is expected to be nearly empty of electrons under equilibrium conditions in ZnTe(O).

Formato

application/pdf

Identificador

http://oa.upm.es/35793/

Idioma(s)

eng

Publicador

E.T.S.I. Telecomunicación (UPM)

Relação

http://oa.upm.es/35793/1/INVE_MEM_2014_190197.pdf

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6811146

info:eu-repo/semantics/altIdentifier/doi/10.1109/JPHOTOV.2014.2305903

Direitos

http://creativecommons.org/licenses/by-nc-nd/3.0/es/

info:eu-repo/semantics/openAccess

Fonte

IEEE Journal of Photovoltaics, ISSN 2156-3381, 2014, Vol. 4, No. 4

Palavras-Chave #Electrónica #Telecomunicaciones
Tipo

info:eu-repo/semantics/article

Artículo

PeerReviewed