Hot-spot formation in stacks of intrinsic Josephson junctions in Bi2Sr2CaCu2O8

Abstract

We have studied experimentally and numerically temperature profiles and the formation of hot spots in intrinsic Josephson junction stacks in Bi2Sr2CaCu2O8 (BSCCO). The superconducting stacks are biased in a state where all junctions are resistive. The formation of hot spots in this system is shown to arise mainly from the strongly negative temperature coefficient of the c-axis resistivity of BSCCO at low temperatures. This leads to situations where the maximum temperature in the hot spot can be below or above the superconducting transition temperature Tc. The numerical simulations are in good agreement with the experimental observations.

Electrical Breakdown in a V2O3 device at the Insulator to Metal Transition

“…The primary cause for these phenomena is a strong change in the resistivity vs. temperature characteristic of the material used for the device under investigation. These phenomena can be observed in large number of different kind of devices: There is the hot-spot in a superconducting microbridge [19,22,23], the pinch caused by thermal breakdown in a negative temperature coefficient thermistor (NTC) [24,25], the domains in a two valley semi-conductor used in a Gunn-diode [18], the hot spot in a large BSCCO-mesa used as a THz-emitter [26][27][28][29] or the filaments in a VO 2 device [7,30] at the metal-insulator transition, to name only a few examples. In the following, only the basics of this topic necessary to understand the supplemented paper are provided.…”