Investigation of photoconductivity and mobility in TlBr

Shorohov

et al. 2015

IEEE Trans. Nucl. Sci.

Carrier transport properties of TlBr crystals grown using the Bridgman method were investigated by the time-of-flight technique. The electron and hole mobilities were measured as cm Vs and cm Vs respectively at room temperature. The temperature dependence of the electron mobility increases with decreasing temperature as approximated by a well-known empirical formula reflecting the reciprocal of the LO-phonon density.

Section: Introductionmentioning

confidence: 98%

“…In relation to the development of detectors, ionic conduction of the material has been investigated as a cause of instability in the detector's performance [5], [6]. In these publications, temperature dependence of the hole Hall mobility was measured.…”

Section: Introductionmentioning

confidence: 99%

Time-of-Flight Measurements on TlBr Detectors

Shorohov

et al. 2015

IEEE Trans. Nucl. Sci.

“…Accordingly, various techniques have been employed to characterize the crystalline structure, including electron backscattered diffraction and positron annihilation. (2) Also, the dynamics and transport properties of electron-hole pairs in TlBr crystals have been characterized using photoconductivity, (3)(4)(5)(6)(7)(8) photoluminescence, (9)(10)(11) cathodoluminescence, (12) and X-ray-induced radioluminescence. (10,13) We have recently applied pump-probe-type transient absorption spectroscopy to elucidate the dynamics of the electron-hole pairs produced by pulsed electron beams (14) we discussed the origin of the transient absorption and some of the dynamics.…”

Section: Introductionmentioning

confidence: 99%

Recombination Dynamics of Electron–Hole Pairs in TlBr Crystals Probed by Transient Absorption Spectroscopy Using Pulsed Electron Beams

Koshimizu,

Muroya,

Nogami

et al. 2024

Sensors and Materials

To develop semiconductor detectors based on TlBr with excellent energy resolution at high yields, a variety of characterization methods for TlBr crystals are necessary. Among the various methods based on excitation by photons or ionizing radiation, we chose transient absorption measurements after the irradiation of pulsed electron beams to analyze the recombination dynamics of electron-hole pairs generated by the electron beams. The decay behavior of the transient absorption depended on the pulse intensity and was satisfactorily fitted with a decay function based on bimolecular recombination dynamics. The bimolecular recombination coefficients obtained from the fitting were similar for the samples cut from different parts of a crystal boule. Assuming that the recombination occurred through Shockley-Read-Hall bimolecular recombination via electronic levels of defects within the bandgap, the result indicates that the concentrations of the defects responsible for the recombination were similar for the samples out from different parts of the crystal boule.

“…(8) Photoconductivity studies have revealed the transport properties of the optically produced electron-hole pairs. (9)(10)(11)(12) Similarly, photoluminescence, cathodoluminescence, and scintillation spectroscopies with steady-state and time-resolved measurements at different temperatures have revealed lattice imperfections such as point defects and dislocations. (13)(14)(15)(16) In this study, we employed transient absorption spectroscopy to characterize TlBr crystals.…”

Section: Introductionmentioning

confidence: 99%

Transient Absorption Spectroscopy of TlBr Crystals Using Pulsed Electron Beams

Koshimizu

Muroya

Yamashita

et al. 2020

Sensors and Materials

We analyzed the transient absorption properties of TlBr crystals using pulsed electron beams as excitation sources. We observed transient absorption spectra and temporal profiles on the pico-and nanosecond scales and compared the results obtained for TIBr crystals that are empirically appropriate with those that are inappropriate for semiconductor detectors. The results showed negligible differences in properties between the two types of crystal, which indicates that their trap center concentrations were similar. A transient absorption band was observed at approximately 1160 nm on the nanosecond scale, while its short-wavelength tail was observed on the picosecond scale. The absorption band is attributed to the localized holes at Tl + that are stabilized by some defects. In contrast, no absorption band attributable to localized electron centers was observed, indicating that while hole transport is hindered by defects, electron transport is not.