Physics Van 3-site Navigational Menu

Physics Van Navigational Menu

Q & A: superconducting phase

Learn more physics!

Most recent answer: 09/04/2010
Q:
I just found out that the factor which makes a material superconducting or not is not only temperature, but also pressure. Since phases of matter are influenced by both temperature and pressure, is it possible if superconductor is also a phase of matter?
- Ray (age 24)
A:
Yes, definitely. In physics, we speak of many different phases of matter. Any different states which have some qualitatively different feature are different phases. An example of a qualitative difference would be the presence or absence of large-scale magnetism, or of the less familiar type of electronic order found in a superconductor. The conversion between different phases occurs under well-defined conditions of temperature, pressure, magnetic field, etc., and is called a phase transition.

The familiar phase transitions discussed in high school (among gas, liquid, and solid) are a small subset of the many transitions possible. For example, solids can exist in may different crystal structures, with phase transitions between them. So really there isn't a single solid phase, but a large family of solid phases.

There are in fact several distinct types of superconducting order, constituting different phases.  Likewise there are phase transitions in and out of various magnetic phases, etc.

Mike W.

(published on 09/04/2010)

Follow-up on this answer.