Given the challenges in experimental studies of uranium, the heaviest naturally occurring metal, we present ﬁrst-principles calculation for the spin-dependent transport. Showing the largest atomic spin-orbit coupling we explore the ability of various crystal phases to maximise the charge to spin conversion using a full relativistic Korringa-Kohn-Rostoker Greens function method. The transport theory is based on a semi classical description where intrinsic and extrinsic, skew scattering, contributions can be separated easily. In addition to the various crystal phases we analyse the eﬀect of substitutional impurities for γ, hcp, as well as the α-phase. We predict a very high, 104(Ωcm)−1, spin Hall conductivity for the meta-stable hcp-U phase, a giant value 5 times larger than for the conventional spin Hall material Pt. We estimated an eﬃciency of charge-to-spin current conversion of up to 30%. The spin diﬀusion length, a crucial parameter in any application, is predicted to be in the range from 3−6.5nm, compatible with other charge-to-spin conversion materials. Relating our work to the sparse experimental results, our calculations suggest a γ phase in the thin ﬁlm rather than the experimentally expected α phase.
- Spin-orbit coupling
- Transport phenomena