Size Effect in the High-Field Magnetoconductivity of Pure Metal Single Crystals

The magnetoresistivity of tungsten single crystals with a residual resistivity ratio of up to 70,000 was measured in the temperature range from 4.2 to 55 K in a magnetic field of 10 T. The size effect, i.e., the linear dependence of the magnetoconductivity on the inverse sample dimensions, has been observed in the high-field magnetoconductivity. The experiments show that this phenomenon can be used to separate and study the surface and volume contributions to the magnetoresistivity of pure single crystals of compensated metals from liquid helium temperature up to approximately 25 K. It is shown that the specular reflection coefficient of the conduction electrons for pure metals in high magnetic fields can be determined in this way.