HgBa$_{2}$CuO$_{4+delta}$ (Hg1201) has been shown to be a model cuprate for scattering, optical, and transport experiments, but angle-resolved photoemission spectroscopy (ARPES) data are still lacking owing to the absence of a charge-neutral cleavage
plane. We report on progress in achieving the experimental conditions for which quasiparticles can be observed in the near-nodal region of the Fermi surface. The d-wave superconducting gap is measured and found to have a maximum of 39 meV. At low temperature, a kink is detected in the nodal dispersion at approximately 51 meV below the Fermi level, an energy that is different from other cuprates with comparable T$_c$. The superconducting gap, Fermi surface, and nodal band renormalization measured here provide a crucial momentum-space complement to other experimental probes.
Measurements and modeling of electron spin transport and dynamics are used to characterize hyperfine interactions in Fe/GaAs devices with $n$-GaAs channels. Ga and As nuclei are polarized by electrically injected electron spins, and the nuclear polar
ization is detected indirectly through the depolarization of electron spins in the hyperfine field. The dependence of the electron spin signal on injector bias and applied field direction is modeled by a coupled drift-diffusion equation, including effective fields from both the electronic and nuclear polarizations. This approach is used to determine the electron spin polarization independently of the assumptions made in standard transport measurements. The extreme sensitivity of the electron spin dynamics to the nuclear spin polarization also facilitates the electrical detection of nuclear magnetic resonance.
