Charis Quay

Spin imbalance and spin-charge separation in a mesoscopic superconductor

Injection of spin-polarized electrons into a superconductor leads to both spin and charge imbalance. If charge relaxation occurs faster than spin relaxation, it is possible to observe excess spin at almost no extra charge.

Frequency-Domain Measurement of the Spin Imbalance Lifetime in Superconductors

We have measured the lifetime of spin imbalances in the quasiparticle population of a superconductor

Quasiparticle spin resonance and coherence in superconducting aluminium

({\ensuremath{\tau}}_{s})

Superconductor spintronics: modeling spin and charge accumulation in out-of-equilibrium NIS junctions subjected to Zeeman magnetic fields

in the frequency domain. A time-dependent spin imbalance is created by injecting spin-polarized electrons at finite excitation frequencies into a thin-film mesoscopic superconductor (Al) in an in-plane magnetic field (in the Pauli limit). The time-averaged value of the spin-imbalance signal as a function of excitation frequency

Spectroscopy of bulk and few-layer superconducting NbSe 2 with van der Waals tunnel junctions

{f}_{\text{rf}}

Tunneling into the vortex state of NbSe

shows a cutoff at

_2

{f}_{\text{rf}}\ensuremath{\approx}1/(2\ensuremath{\pi}{\ensuremath{\tau}}_{s})

with van der Waals junctions.

. The spin-imbalance lifetime is relatively constant in the accessible ranges of temperatures, with perhaps a slight increase with increasing magnetic field. Taking into account sample thickness effects,

Hard superconducting gap and vortex-state spectroscopy in NbSe

{\ensuremath{\tau}}_{s}

_2

is consistent with previous measurements and of the order of the electron-electron scattering time