Wire member and method of fabricating same
A wire member adapted to be used in a detection coil of an NMR spectrometer's probe. The wire member has a sleeve made of a copper tube having a high electrical conductivity, strands made of platinum, and a thin film of gold or rhodium formed on the surface of the sleeve by plating. The strands are mounted inside the sleeve and have a cross section to cancel the magnetic susceptibility due to the sleeve. The thin film cancels the total magnetic susceptibility of the sleeve and strands.
1. A wire member for use in a detection coil that detects an NMR (nuclear magnetic resonance) signal from a sample, said wire member comprising:
at least one first wire component made of a first metal having a high electrical conductivity;
at least one second wire component made of a second metal having a magnetic susceptibility opposite in sign to magnetic susceptibility of said first wire component, said second wire component disposed inside said first wire component; and
a thin film less than about 1 micron thick made of a third metal, said third metal having a magnetic susceptibility opposite in sign to a total magnetic susceptibility of said first and second wire components,
wherein said first wire component has a tubular shape and holds said second wire component therein, and wherein said thin film is formed on a surface of said first wire component.
2. The wire member of claim 1 , wherein said first metal is copper, said second metal is platinum, and said third metal is one of gold and rhodium.
3. The wire member of claim 1 , wherein said first metal has a damagnetic susceptibility, said second metal has a paramagnetic susceptibility, and said third metal has one of a diamagnetic susceptibility and a paramagnetic susceptibility.