TITLE:
Mechanical and Dielectric Properties of InTe Crystals
AUTHORS:
Teena Mathew, Ayyappacharuparambil Gopalanachary Kunjomana, Keelapattu Munirathnam, Kunnath Appukuttan Chandrasekharan, Muthukrishnan Meena, Chelliah Kamalakshiammal Mahadevan
KEYWORDS:
Indium Telluride; Bridgman Technique; Microhardness; Dielectric Constant; Dielectric Loss; AC Conductivity
JOURNAL NAME:
Crystal Structure Theory and Applications,
Vol.1 No.3,
December
31,
2012
ABSTRACT:
The mechanical properties of indium telluride (InTe) crystals grown by the Bridgman technique were investigated at room temperature using a Vickers hardness tester. The microhardness is observed to vary nonlinearly with the applied load, 10 - 100 g. The cleaved ingots are found to have high value of microhardness (222.44 kg/mm2 at a load of25 g), which reflects an appreciable degree of strength due to their covalent bonding and homogeneity. The studies revealed that the dislocations in the grown crystals offered a resistance to fresh dislocations due to interaction. At higher loads, plastic deformation induces by slip, exhibiting a decrease in hardness from the peak value. The dielectric constant and dielectric loss of indium telluride crystals were evaluated in the frequency range, 1 kHz - 1 MHz for different temperatures (35oC - 140oC). The frequency dependence of AC conductivity was analyzed as a function of temperature. The effect of temperature and frequency on the dielectric response of InTe crystals has been assessed on their cleavage faces and the obtained results are discussed.