On the galvanomagnetic properties of α -uranium at low temperatures

The magnetoresistance of and Hall effect in polycrystalline α - U in the temperature interval 4.2 – 77 K and transverse magnetic fields B to 4 T have been investigated. It is found that below 43 K the Hall coefficient R H of α -uranium depends on the magnetic field. The strong temperature dependence of the R H below 43 K which is due to three charge-density-wave type transitions is confirmed. Above 43 K the Hall coefficient is weakly temperature dependent and is independent of the magnetic field. The magnetoresistance is approximately parabolic and does not exhibit any indications of saturating even in strong fields. The application of the isotropic two-band model made it possible to evaluate qualitatively the dependence of the charge carrier density n and mobility μ on the magnetic field (to 4 T ) and on the temperature in the interval 4.2 – 77 K . It is shown that charge-density-wave type transitions at T < 43 K are accompanied by a considerable change in n and μ . It is found that at 4.2 K n and μ depend strongly on the magnetic field from 0 to 4 T . There is no such dependence at temperatures T ⩾ 50 K .