Superconductivity and other macroscopic quantum phenomena
Abstract
A diverse class of macroscopic quantum phenomena including superconductors, superfluid helium, lasers, and quasi-one-dimensional conductors, exhibiting a common feature of macroscopic occupation of a single quantum state, is presented. Some of the features that are considered important in the design of structures of smaller scale are the following: the quantum states of macroscopic bodies are discrete; there can be macroscopic occupation of one state; and to define a quantum system, it is necessary to specify the state of macroscopic occupation as well as the velocity of the walls with which the system comes to thermal equilibrium. If many electrons are involved in a phase-coherent step, it is suggested that the energy involved can be much larger than the thermal energy even though the energy per electron may be smaller.
- Publication:
-
Physics Today
- Pub Date:
- December 1990
- DOI:
- 10.1063/1.881218
- Bibcode:
- 1990PhT....43l..25B
- Keywords:
-
- Quantum Mechanics;
- Superconductivity;
- Direct Current;
- Electric Conductors;
- Landau Factor;
- Semiconductor Lasers;
- Superfluidity;
- Two Fluid Models;
- Physics (General)