Superconductivity of Metallic Indium Telluride

Abstract

Fig. 1. X-ray diffraction patterns for allotropes ofInTe; ordinate, degrees (20); abscissa, relative intensity. Left trace: InTe(II), cubic form; right trace: In? Te (I), tetragonal form. taken at 25?C, Fig. 1, exhibits no dif? fraction lines corresponding to In, Te, or InTe(I) thus indicating that the conversion was essentially complete. The cubic structure with six nearest neighbors causes an insufficiency in the valence electrons for covalent bonding, which we believe leads to a condition of resonance equivalent to the metallic state (4). The physical properties are interest? ing. Whereas the InSb metal is very hard, nearly as hard as steel, the InTe metal is very soft and friable. It is readily scratched by glass. Our preparations have consisted of crystals of mean dimensions of 2000 A as judged from the width of the x-ray lines. The most remarkable of the obvious physical properties is the beautiful light blue color which the new metal shows on all its crystalline faces. This light blue metallic luster changes to a darker blue when the metal is cooled to -197?C. Abstract. Metallic indium telluride is a superconductor with a transition tem? perature of 2.18?K. The critical mag? netic field is about 800 gauss. Superconductivity in metallic InTe prepared and stabilized at atmospheric pressure in the way described by Dar? nell, Libby, and Yencha (1) has been observed by the same method as pre? viously reported for the measurement of metallic InSb (2). In order to obtain a good filling factor for the measure? ment coil, seven specimens about 5 mm in diameter with lengths ranging from 1 mm to 12 mm were measured simul? taneously. The total length was about 25 mm. The specimens were presumably polycrystalline. The zero-field transition temperature To appeared to be at 2.18?K and showed, contrary to InSb, a relatively sharp transition width of about 0.01 ?K. The sharpness of the transition might indicate that the specimens were not highly strained. Measurements in mag? netic fields showed, as might be ex? pected from the non-ideal geometry, that the intermediate state extended over a fairly wide range.Fig. 1. The critical magnetic field as a func? tion of temperature for InTe (II) (metal? lic indium tellurium).The results are shown in Fig. 1. The lower curve represents the magnetic field at which normal conductivity started to appear at a given temper? ature. The upper curve represents the field at which the transition to the normal state was completed for the same temperature. Extrapolation of the curves to zero degrees would indi? cate a critical field Hc(0) of about 800 gauss. Abstract.Cholinergic substance exists in homogenates of caudal neuro? secretory storage organs of fish. The caudal organs of fresh-water fish con? tain about 10 times the amount found in caudal organs of marine fish. The substance in the caudal organ of the corp is more than 100 times as con? centrated as that in the brain.

Evolution of Electronic States and Emergence of Superconductivity in the Polar Semiconductor GeTe by Doping Valence-Skipping Indium

“…Historically, it was in the early 1960s that Cohen theoretically predicted superconductivity in many-valley semiconductors and semimetals 1 due to their peculiar band structure, such as GeTe, SnTe, and SrTiO 3 [2][3][4] , which was experimentally confirmed soon after. In particular, SnTe, which has recently regained much attention as a topological crystalline insulator 5,6 , exhibits superconductivity below critical temperatures T c of less than 300 mK. Interestingly, the superconducting transition temperature is strongly enhanced by In doping in its cubic structure [7][8][9] .…”

Tailoring band structure and band filling in a simple cubic (IV, III)-VI superconductor

“…However, when synthesizing InTe under a pressure of p ∼ 3 GPa, cubic InTe with rock-salt struc-ture forms and is metastable at room temperature. Moreover it superconducts below T c ∼ 3 K [21,22], motivating this study to synthesize Sn 1−x In x Te for x ≥ 0.5 and their Se-codoped analogues by employing a high-pressure synthesis method.…”

High-Pressure Transitions in A (III) B (VI) Compounds: Indium Telluride

“…After the column is in equilibrium with solvent and solute at concentration C, this concentration is changed stepwise to a slightly higher or lower value and the retention volume of the concentration step (more accurately, of the center of gravity of the step) is measured. It is readily shown by a material balance written around the column that the adjusted retention volume of the step, VR', at sufficient dilution is related to the slope of the isotherm by dC/dC = Vi'/VL (5) provided that the step has been made so small that the isotherm slope remains essentially unchanged by the concentration change. To verify that this condition is met, two measurements may be made by changing the concentration in the first from C to C + AC and in the second from C to C -AC; both retention volumes should be the same within the tolerable error.…”