37 research outputs found
Spin relaxation in Rashba rings
Spin relaxation dynamics in rings with Rashba spin-orbit coupling is
investigated using spin kinetic equation. We find that the spin relaxation in
rings occurs toward a persistent spin configuration whose final shape depends
on the initial spin polarization profile. As an example, it is shown that a
homogeneous parallel to the ring axis spin polarization transforms into a
persistent crown-like spin structure. It is demonstrated that the ring geometry
introduces a geometrical contribution to the spin relaxation rate speeding up
the transient dynamics. Moreover, we identify several persistent spin
configurations as well as calculate the Green function of spin kinetic
equation
Bifurcation analysis of a TaO memristor model
This paper presents a study of bifurcation in the time-averaged dynamics of
TaO memristors driven by narrow pulses of alternating polarities. The analysis,
based on a physics-inspired model, focuses on the stable fixed points and on
how these are affected by the pulse parameters. Our main finding is the
identification of a driving regime when two stable fixed points exist
simultaneously. To the best of our knowledge, such bistability is identified in
a single memristor for the first time. This result can be readily tested
experimentally, and is expected to be useful in future memristor circuit
designs