Evidence for light-induced hole polarons in LiNbO3.
Transient light-induced absorption in LiNbO3 is observed in the blue-green spectral range after pulsed illumination with 532 nm. Its buildup and decay in Fe-doped LiNbO3 is satisfactorily described by a sum of two stretched exponential functions. For undoped LiNbO3, however, only one stretched exponential decay is observed. These experimental results are explained by the formation of both small Nb(Li)4+ electron polarons and O- hole polarons. The mechanism is discussed on the basis of a proposed band scheme.
Herth
P
P
Institut für Mineralogie, Universität zu Köln, 50674 Köln, Germany.
Granzow
T
T
Schaniel
D
D
Woike
Th
T
Imlau
M
M
Krätzig
E
E