Pinch Effect in Indium Antimonide

Abstract

The critical current at which pinching occurs in indium antimonide has been measured by three independent methods: (a) by noting the current at which the pinched current-voltage characteristic deviates from the unpinched characteristic that is obtained in the presence of a longitudinal magnetic field H, using crystals of sufficiently high resistance for the avalanche breakdown current to be considerable, before pinching sets in, as the electric field is increased; (b) by noting the current at which the magnetoresistance, as a function of H, shows a change in its behavior; and (c) from a study of the critical current as a function of H. The three methods lead to a value for the critical pinching current of 4-5 amp. This current is the same for both single-crystal and polycrystalline samples, and is insensitive to small changes in the donor concentration or cross-sectional area of the crystal. The value of the critical current leads to a mean carrier temperature of 0.04 ev in avalanche breakdown. An irregular form of noise is observed when the crystal is operated in the transition region between the pinched and unpinched conditions, and it is thought that this noise is caused by pinching-unpinching instabilities.

The quantum pinch effect in semiconducting quantum wires: A bird’s-eye view

“…Thus a metal with only electrons contributing to the conduction is a poor option. The 1960's had seen considerable experimental [6][7][8][9][10][11][12][13][14][15] and theoretical [16][17][18][19] efforts focused on studying pinch effect in the bulk SSP, with instabilities manifesting themselves as voltage and current oscillations at frequencies up to 50 MHz. Notwithstanding the SSP had been imbued to a greater extent by the research pursuit for the pinch effect in the GSP, the subject did not gain sufficient momentum because the early 1970's had begun to offer the condensed matter physicists with the new venues to explore: the semiconducting quantum structures with reduced dimensions such as quantum wells, quantum wires, quantum dots, and their periodic counterparts.…”

“…This tells us that in a quantum wire the maximum of charge density lies at r/R = 0.3271 instead of exactly at the axis. Note that the classical pinch effect in conventional (3D) SSP [6][7][8][9][10][11][12][13][14][15][16][17][18][19] does not share any such feature. Very close to the axis and to the surface of the quantum wire, the minimum of the current density is smallest but still nonzero.…”

Instabilities and Turbulence in Semiconductors

“…The first category of instabilities contains : a) the pinch instabilities whichare analogous to those occuring in gas discharges and which have been observed at low temperatures in InSb in 1961 by Glicksman and Powlus [l] and Chynoweth and Murray [2]. b) the Gunn-effect and various other instabilities which are caused by a nonmonotonic field dependence of the carrier mobilities and which generate coherent high frequency oscillations.…”

Quantum pinch effect

“…Thus a metal with only electrons contributing to the conduction is a poor option. The 1960's had seen considerable experimental [6][7][8][9][10][11][12][13][14][15] and theoretical [16][17][18][19] efforts focused on studying pinch effect in the bulk SSP, with instabilities manifesting themselves as voltage and current oscillations at frequencies up to 50 MHz.…”