Fine structure of the exciton band and anisotropic optical constants in scheelitePbWO4crystals

Optical anisotropy and electronic structures ofCdMoO4andCdWFujita1, Itoh2, Katagiri3 et al. 2008Phys. Rev. BSelf Cite

“…In the cases of CdWO 4 and ZnWO 4 , a significant contribution of the metal states is found at the bottom of the conduction band, while their contributions are negligible on the top of the valence band. The calculation results explain well the experimental spectra in the fundamental absorption-edge region in PbWO 4 , 13 CaWO 4 , 14 and ZnWO 4 . 18 Only recently, x-ray photoelectron spectroscopy ͑XPS͒ studies have been carried out for these tungstates to clarify the electronic structures of the valence bands and outermost-core levels.…”

“…[12][13][14] A marked dichroism of the exciton band with some fine structures has been found in PbWO 4 , which can be explained in terms of the cationic transition in Pb 2+ ion placed in the uniaxial crystal field. 13 This result indicates a substantial contribution of the Pb state to the top of the valence band and the bottom of the conduction band in PbWO 4 . From a comparative study of CaMoO 4 and CaWO 4 , 14 we confirmed that the lowest absorption spectra of Ca compounds are as-cribed to the transitions from the O 2p valence band to the Mo 4d or W 5d conduction band.…”

Observation of polarized luminescence from Jahn–Teller split states of self-trapped excitons in PbWO4by time-resolved spectroscopy

“…The 266 nm light locates in the high-energy region of the exciton absorption band of PWO [23,24]. The pulse width, repetition rate and power density on the sample surface were 7 ns, 10…”

Photo-stimulated luminescence and photo-induced infrared absorption in ZnWO4

“…If this assumption is correct, it is reasonable to assign the lowest reflection peak at 4.37 eV to the excitonic transition in Zn 2+ ions. In this connection, it is worth noting that the oscillator strength of the exciton transition in ZnWO 4 is significantly small compared with that in PbWO 4 (Fujita et al, 2002), where the cationic exciton originates from the 6s → 6p transition in Pb 2+ ions.…”