Glossary J-N

Jc Critical current density. Maximum current density in a material that allows it to remain in the superconducting state.
JE Engineering critical current – critical current density calculated for the entire wire, not just the superconductor material. Includes effects of buffers, substrate.
Josephson Junction A thin layer of insulating material sandwiched between 2 superconducting layers. Electrons tunnel through this non-superconducting region via the Josephson effect. Key components in superconductor electronics and computing. (from
Laser Ablation  
Large-grain HTS HTS produced in relatively large thicknesses, composed of large crystals. JC is much lower than in thin film coated conductors, although it can be increased with the use of chemically-created pinning centers. Large grain HTS is frequently used to make permanent magnets. It is difficult to make long lengths of large grain HTS, and it is therefore not a candidate for power transmission.
LHC Large Hadron Collider at CERN
LL Load losses
Lorentz microsuperconductoropy A simple method by which the domain walls of magnetic materials can be made visible in a qualitative fashion.
LPE Liquid phase epitaxy
LTS Low temperature superconductor, metallic materials with a TC of less than 30 K
Maglev Magnetic levitation, i.e. for trains. Some use electromagnets, there are superconductor magnet prototypes.
Magnesium diboride A cheap, "off-the-shelf" chemical compound that can be made into a superconductor. Magnesium diboride becomes superconducting at -234 °C (39K) - much higher than previously observed in relatively simple and readily available compounds, and between conventional LTS and HTS temperatures. Also MgB2.
Magnetic Field  
Magnetic Flux  
Magnetoencephalography Imaging of the electromagnetic field of the brain.
MCP Melt Cast Processed,
MEG See Magnetoencephalography – imaging of the electromagnetic field of the brain.
Meissner effect The Meissner effect is the effect by which a weak magnetic field decays rapidly to zero in the interior of a superconductor. The distance to which the field is active is known as the london penetration depth. This active exclusion of magnetic fields is distinct from perfect diamagnetism, as the magnetic field will be zero inside the superconductor regardless of what it was before the material became superconducting. The Meissner effect is one of the defining features of superconductivity, and its discovery served to establish that the onset of superconductivity is a phase transition. It was discovered by Walther Meißner and Robert Ochsenfeld in 1933. (wikipedia)
MFCL Matrix fault current limiter. See Fault Current Limiter.
M-G Motor-generator
MHD Magnetohydrodynamic – Having to do with the study of magnetic fluids, i.e. plasma.
MILD multiple-in-line-damage. See flux pinning.
MOCVD Metallorganic Chemical Vapor Deposition, producing a thin film by depositing a precursor material evaporated onto a substrate.
MOD Metal organic deposition. Precursor material deposited in liquid form onto substrate, baked to form YBCO.
MOV Metal oxide varistor
MPMG Melt powder melt growth
MRI Magnetic resonance imaging. The body is exposed to a strong magnetic field, which aligns hydrogen atoms in the body's water and fat molecules. Radio frequency pulses make the atoms absorb and release energy that can be detected and displayed graphically by a computer.
multi-plume A method for manufacturing superconducting materials where the superconductors are sprayed onto the metal substrate.
multi-turn A method for manufacturing superconducting wire where the process is sped up by applying the superconducting material to multiple turns of the wire at the same time.
Naming superconductors For cuprate superconductor. The scheme chosen uses four numbers. The first denotes the number of insulating layers between adjacent conducting blocks. The second represents the number of spacing layers between identical CuO2 blocks. The third gives the number of layers that separate adjacent CuO2 planes within the conducting block. And, the fourth is the number of CuO2planes within a conducting block.
Nano-structure A nanostructure is an intermediate size between molecular and microscopic (micrometer-sized) structures.
Nd-422 Nd4Ba2Cu2Ox
NLL No-load loss
NMR Nuclear magnetic resonance
NQR Nitrogen nuclear quadrupole resonance. The use of the resonant frequency of atoms to determine the molecular structure of a material.