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arXiv · 2112.07733

Emergence and Manipulation of non-equilibrium Yu-Shiba-Rusinov states

Jasmin Bedow·Eric Mascot·Dirk K. Morr
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Abstract

The experimental advances in the study of time-dependent phenomena has opened a new path to investigating the complex electronic structure of strongly correlated and topological materials. Yu-Shiba-Rusinov (YSR) states induced by magnetic impurities in $s$-wave superconductors provide an ideal candidate system to study the response of a system to time-dependent manipulations of the magnetic environment. Here, we show that by imposing a time-dependent change in the magnetic exchange coupling, by changing the relative alignment of magnetic moments in an impurity dimer, or through a periodic drive of the impurity moment, one can tune the system through a time-dependent quantum phase transition, in which the system undergoes a transition from a singlet to a doublet ground state. We show that the electronic response of the system to external perturbations can be imaged through the time-dependent differential conductance, $dI(t)/dV$, which, in analogy to the equilibrium case, is proportional to a non-equilibrium local density of states. Our results open the path to visualizing the response of complex quantum systems to time-dependent external perturbations.

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Jasmin Bedow, Eric Mascot, Dirk K. Morr. 2021-12-14. Emergence and Manipulation of non-equilibrium Yu-Shiba-Rusinov states. https://arxiv.org/abs/2112.07733

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