Mixed conduction and anisotropic single oscillator parameters in low dimensional TlInSe2 crystals

Date

2013-08-15

Author

QASRAWI, ATEF FAYEZ HASAN
Hasanlı, Nızamı

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

122
views

0
downloads

Due to the importance of the TlInSe2 crystal as neutron and gamma-ray detectors, its electrical and dispersive optical parameters have been investigated. Particularly, the anisotropic current conduction mechanism in the temperature region of 100-350 K and the room temperature anisotropic dispersive optical properties were studied by means of electrical conductivity and optical reflectance, respectively. It has been shown that the mixed conduction is the most dominant transport mechanism in the TlInSe2 crystals. Particularly, when the electric field is applied perpendicular to the crystal's c-axis, the main dominant current transport mechanism is due to the mixed conduction and the variable range hopping above and below 160 K, respectively. When the electric field is applied parallel to the crystal's c-axis, the electrical conductivity is dominated by the thermionic emission, mixed conduction and variable range hopping at high, moderate and low temperatures, respectively. The optical reflectivity analysis in the wavelength range 210-1500 nm revealed a clear anisotropy effect on the dispersive optical parameters. Particularly, the static refractive index, static dielectric constant, dispersion energy and oscillator energy exhibited values of 2.50, 6.24, 20.72 eV and 3.96 eV, and values of 3.05, 9.33, 39.27 eV and 4.72 eV for light propagation parallel and perpendicular to the crystal's c-axis, respectively. Moreover, the frequency dependence of the dielectric constant, epsilon(omega), reflected strong dielectric anisotropy that exhibit maximum epsilon(omega) value of 38.80 and 11.40 at frequencies of 11.07 x 10(14) Hz for light propagation parallel and perpendicular to the crystal's c-axis, respectively. The anisotropy in the epsilon(omega) makes the TlInSe2 crystals attractive to be used as nonvolatile static memory devices.

Subject Keywords

General Materials Science, Condensed Matter Physics

URI

https://hdl.handle.net/11511/48958

Journal

MATERIALS CHEMISTRY AND PHYSICS

DOI

https://doi.org/10.1016/j.matchemphys.2013.04.025

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Visible photoluminescence from chain Tl4In3GaSe8 semiconductor Hasanlı, Nızamı (IOP Publishing, 2006-07-05) The emission band spectra of undoped Tl4In3GaSe8 chain crystals have been studied in the 16-300 K temperature range and the 535-740 nm wavelength range. Two visible photoluminescence bands centred at 589 and 633 nm were observed at T = 16 K. Variations of both bands have been investigated over a wide range of laser excitation intensity ( 3 x 10(-4) -1.2 W cm(-2)). Radiative transitions with energies of 2.10 and 1.96 eV from two upper conduction bands to two shallow acceptor levels (0.03 and 0.01 eV), respec...
Electron-lattice interaction scattering mobility in Tl(2)InGaSe(4) single crystals QASRAWI, ATEF FAYEZ HASAN; Hasanlı, Nızamı (IOP Publishing, 2008-04-16) In this work, the dark electrical resistivity, charge carrier density and Hall mobility of Tl(2)InGaSe(4) single crystal have been recorded and analyzed to investigate the dominant scattering mechanism in the crystal. The data analyses have shown that this crystal exhibits an extrinsic n-type conduction. The temperature-dependent dark electrical resistivity analysis reflected the existence of two energy levels as 0.396 and 0.512 eV, being dominant above and below 260 K, respectively. The temperature depende...
Optical anisotropy in GaSe Seyhan, A; Karabulut, O; Akınoğlu, Bülent Gültekin; Aslan, B; Turan, Raşit (Wiley, 2005-09-01) Optical anisotropy of the layer semiconductor GaSe has been studied by photoluminescence (PL) and Fourier Transform Infrared Spectroscopy (FTIR). The PL spectra are dominated by two closely positioned emission bands resulting from the free exciton and the bound exciton connected direct band edge of GaSe. Photoluminescence and transmission spectra of GaSe crystals have been measured for two cases in which the propagation vector k is perpendicular (k perpendicular to c) and parallel to the c-axis (k//c). Peak...
Resonant Raman scattering near the free-to-bound transition in undoped p-GaSe Hasanlı, Nızamı; Ozkan, H (Wiley, 2001-01-01) Raman spectra of GaSe layered crystal have been measured using a He-Ne laser and temperature tuning the free-to-bound gap in the range 10-290 K. Resonance enhancement of E'((12)) mode has been observed for both incident and scattered photon energies equal to the free-to-bound transition energy.
Temperature-tuned band gap energy and oscillator parameters of Tl2InGaSe4 semiconducting layered single crystals Hasanlı, Nızamı (Wiley, 2009-03-01) The optical properties of Tl2InGaSe4 layered single crystals have been studied through the transmission and reflection measurements in the wavelength range of 500-1100 nm. The analysis of room temperature absorption data revealed the presence of both optical indirect and direct transitions with band gap energies of 1.86 and 2.05 eV, respectively. Transmission measurements carried out in the temperature range of 10-300 K revealed that the rate of change of the indirect band gap with temperature is gamma = -4...

Citation Formats

A. F. H. QASRAWI and N. Hasanlı, “Mixed conduction and anisotropic single oscillator parameters in low dimensional TlInSe2 crystals,” MATERIALS CHEMISTRY AND PHYSICS, pp. 63–68, 2013, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48958.