Spin injection and spin relaxation in odd-frequency superconductors

Spin-wave contribution to the nuclear spin-lattice relaxation in triplet superconductors.

We discuss collective spin-wave excitations in triplet superconductors with an easy axis anisotropy for the order parameter. Using a microscopic model for interacting electrons, we estimate the frequency of such excitations in Bechgaard salts and ruthenate superconductors to be 1 and 20 GHz, respectively. We introduce an effective bosonic model to describe spin-wave excitations and calculate th...

Muon Spin Relaxation Studies of Unconventional Superconductors: First-Order Behavior and Comparable Spin-Charge Energy Scales

Since the late 1980s, the muon spin rotation and relaxation (μSR) method has been extensively applied to studies of unconventional superconductors, including high-Tc cuprate, ruthenate, FeAs, organic, and heavy-fermion systems. With its unique sensitivity to static magnetic order in both long-range ordered and random spin systems, μSR has played a leading role in determining magnetic phase diag...

Nuclear spin relaxation rate of disordered px+ ipy-wave superconductors

Spin injection and relaxation in ferromagnet-semiconductor heterostructures

We present a detailed description of spin injection and detection in Fe/AlxGa1−xAs/GaAs heterostructures for temperatures from 2 to 295 K. Measurements of the steady-state spin polarization in the semiconductor indicate three temperature regimes for spin transport and relaxation. At temperatures below 70 K, spinpolarized electrons injected into quantum well structures form excitons, and the spi...

Spin transport in diffusive superconductors

We employ the Keldysh formalism in the quasiclassical approximation to study transport in a diffusive superconductor. The resulting 434 transport equations describe the flow of charge and energy as well as the corresponding flow of spin and spin energy. Spin-flip scattering due to magnetic impurities is included. We find that the spin-flip length is renormalized in the superconducting case and ...