First photoconductivity measurement following photoionization of rare-earth dopant in a dielectric powder

Delayed recombination and excited state ionization of the Ce3+ activator in the SrHfO3 host

“…This is an important step by which the applicability of the method was experimentally established for a class of materials where both an experimental detection of thermal ionization process and the determination of thermal ionization energy are either not feasible by conventional methods [1] or the underlying experiment is too complex and demanding [2,3]. Besides, such a method is of crucial importance in the fast screening of new scintillating materials which are frequently prepared in a powder form using quick and inexpensive technologies, such as solid state sintering.…”

“…For single crystal bulk materials this energy can be determined by photoconductivity measurements, although making ohmic contacts on wide band-gap dielectric materials is a challenging task [1]. "Contactless" techniques that one can also apply to materials in powder form involve the microwave resonator technique [2,3] which is a relatively complex and demanding experiment. Recently, using routine luminescence techniques, two independent experiments enabling detection of thermal ionization and determination of the ionization energy by contactless optical means, were introduced and tested on the Lu 2 Si 2 O 7 :Pr 3+ single crystal [4].…”

Quantum tunneling and low temperature delayed recombination in scintillating materials

“…Conventional photoconductivity measurements can only be applied for single crystalline bulk materials. 'Contactless' methods that one can also apply to materials in powder form include the microwave resonator technique [1,2], or two independent techniques, recently developed, using purely optical means. The first consists of the study of thermally stimulated luminescence (TSL) after UV illumination [4,5].…”

Trapping states and excited state ionization of the Ce3+ activator in the SrHfO3 host

“…For materials in powder form one has to look for 'contactless' alternatives. The microwave resonator technique for the study of photoconductivity in rare-earth-doped dielectric crystals [9] was for the first time used for powder samples in [10]. Another possibility is given by the recently described optical experimental method involving the study of temperature dependence of the TSL signal obtained after UV illumination [11].…”