through the resulting copper spiral, and coolant flows through perforations in the conductors, which are aligned vertically.

bore, magnet:

Inner diameter of a cylindrical magnet where the magnetic field is generated. The bore of a magnet constrains the volume available for experimental use.

coil, magnet(ic):

Electric current in most electromagnets passes through coils of wire. Since the coils of all such magnets are their active component, the terms coil and magnet are often used as synonyms.

coherence length:

Characteristic scale of a Cooper pair in a superconducting material. The coherence length effectively represents the longest distance over which the two electrons of the Cooper pair act in tandem and is typically on the order of 1.5 nm for high-field materials.

Cooper pair:

Entity believed to explain the superconductivity of many materials. A Cooper pair consists of two electrons that are paired together into a new state with zero net charge and angular momentum. Below the superconducting transition temperature, Cooper pairs form a condensate—a macroscopically occupied single quantum state—in which current flows without resistance.


Material such as Cu or Al in which charge carriers can move under the influence of an electrical voltage. Unlike superconductors, conductors have finite, nonzero resistance.

correlated electron systems:

Also strongly correlated electron systems; a many-particle system in which strong interactions between electrons play a crucial role in determining fundamental properties. Electronic correlations can cause striking many-body effects like superconductivity, electronic localization, magnetism, and charge ordering, which cannot be described using the simpler independent particle picture. These properties and dynamics arise from the collective interactions of the electrons with one another.

critical current density (Jc):

At a certain temperature, the maximum electrical current density that a superconductor can carry before it quenches and enters the normal state. In general, as the current flowing through a superconductor increases, the Tc (see below) will usually decrease.

critical field (Hc):

At zero applied current, the maximum magnetic field (at a given temperature) that a superconductor can transport before it quenches and returns

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