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A comprehensive analysis of the electrical conductivity of TlSbSe2 layered compounds prepared using the Bridgman–Stockbarger technique is presented. The temperature dependence of the electrical conductivity of TlSbSe2 and its anisotropy (as measured parallel and perpendicular to the layers) was studied for temperatures between 233 and 353 K. We show that the anisotropy of the electrical conductivity is temperature dependent. The ratio α of the conductivities parallel and perpendicular to the layers obeys an exponential law, with a barrier height of about 37 meV. The dielectric constant and dielectric loss of TlSbSe2 were determined using ohmic Au electrodes in the frequency range 10 Hz–100 kHz and within the temperature interval 233–373 K. The dielectric constant and the dielectric loss are found to decrease with increasing frequency and increase with increasing temperature. These behaviors are due to the polarization mechanisms in the samples. Lastly the activation energy values were derived from dielectric measurements.

A comparison of structure and dielectric properties of TlSbS2 thin films, deposited in different thicknesses (400–4100 A) by thermal evaporation of TlSbS2 crystals that were grown by the Stockbarger–Bridgman technique and the bulk material properties of TlSbS2 are presented. Dielectric constant e 1 and dielectric loss e 2 have been calculated by measuring capacitance and dielectric loss factor in the frequency range 20 Hz–10 KHz and in the temperature range 273–433 K. It is observed that at 1 kHz frequency and 293 K temperature the dielectric constant of TlSbS2 thin films is e 1=1.8–6 and the dielectric loss of TlSbS2 thin films is e 2=0.5–3 depending on film thickness. In the given intervals, both of dielectric constant and dielectric loss decrease with frequency, but increase with temperature. The maximum barrier height W m is calculated from the dielectric measurements. The values of W m for TlSbS2 films and bulk are obtained as 0.56 eV and 0.62 eV at room temperature, respectively. The obtained values agree with those proposed by the theory of hopping over the potential barrier. The temperature variation of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model since it obeys the ω s law with a temperature dependent s (s

Electrical measurements were performed on TlSbSe2 ternary crystals in the temperature range 293–413 K. The obtained I–V characteristics consist of two regions: an Ohmic region at low current densities, and nonlinear regions having negative differential resistance (NDR) at moderate and higher current densities. The nonlinear behavior of the I–V curves was studied at different ambient temperatures. The sample temperature and the threshold voltage of the NDR region were also examined as a function of the ambient temperature. We detected that the investigated samples exhibit threshold-type switching and propose that the switching mechanism has an electronic origin.