High-Field Magnetoresistance of Molybdenum and Tungsten

The transverse magnetoresistance of high-purity samples of Mo and W was measured in magnetic fields up to 83 kOe. No deviation from the quadratic magnetoresistance characteristic of a compensated metal was observed, which shows that the Fermi surfaces of these metals support less than ${10}^{-4\mathrm{}}$ open cyclotron orbits per atom for Mo and ${10}^{-7\mathrm{}}$ per atom for W. The numbers of electrons and holes in W differ by less than 0.07%, which indicates that to this accuracy the number of quasiparticles in a many-body scheme is equal to the number of particles in a one-electron scheme.