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The term "hot electron" comes from the effective temperature term used when modelling carrier density (i.e., with a Fermi-Dirac function) and does not refer to the bulk temperature of the semiconductor (which can be physically cold, although the warmer it is, the higher the population of hot electrons it will contain all else being equal).
For example, a typical white LED output declines 20% for a 50 °C rise in junction temperature. Because of this temperature sensitivity, LED measurement standards, like IESNA’s LM-85 Archived 2017-10-18 at the Wayback Machine, require that the junction temperature is determined when making photometric measurements. [5]
The efficiency of a thermoelectric device for electricity generation is given by , defined as =.. The maximum efficiency of a thermoelectric device is typically described in terms of its device figure of merit where the maximum device efficiency is approximately given by [7] = + ¯ + ¯ +, where is the fixed temperature at the hot junction, is the fixed temperature at the surface being cooled ...
One example of these materials is the semiconductor compound ß-Zn 4 Sb 3, which possesses an exceptionally low thermal conductivity and exhibits a maximum zT of 1.3 at a temperature of 670K. This material is also relatively inexpensive and stable up to this temperature in a vacuum, and can be a good alternative in the temperature range between ...
At the atomic scale, a temperature gradient causes charge carriers in the material to diffuse from the hot side to the cold side. This is due to charge carrier particles having higher mean velocities (and thus kinetic energy) at higher temperatures, leading them to migrate on average towards the colder side, in the process carrying heat across the material.
Meissner Effect (Science from scratch) Short video from Imperial College London about the Meissner effect and levitating trains of the future. Introduction to superconductivity Video about Type 1 Superconductors: R = 0/Transition temperatures/B is a state variable/Meissner effect/Energy gap (Giaever)/BCS model. Meissner Effect (Hyperphysics)
The heat dissipation in integrated circuits problem has gained an increasing interest in recent years due to the miniaturization of semiconductor devices. The temperature increase becomes relevant for cases of relatively small-cross-sections wires, because such temperature increase may affect the normal behavior of semiconductor devices.
The proximity effect is manifested by observations of a supercurrent, i.e. a current flowing through the graphene junction with zero voltage on the junction. By using the gate electrodes the researches have shown that the proximity effect occurs when the carriers in the graphene are electrons as well as when the carriers are holes.