Quasiparticle tunnel electroresistance in superconducting junctions

Abstract

The term tunnel electroresistance (TER) denotes a fast, non-volatile, reversible resistance switching triggered by voltage pulses in ferroelectric tunnel junctions. It is explained by subtle mechanisms connected to the voltage-induced reversal of the ferroelectric polarization. Here we demonstrate that effects functionally indistinguishable from the TER can be produced in a simpler junction scheme-a direct contact between a metal and an oxide-through a different mechanism: a reversible redox reaction that modifies the oxide's ground-state. This is shown in junctions based on a cuprate superconductor, whose ground-state is sensitive to the oxygen stoichiometry and can be tracked in operando via changes in the conductance spectra. Furthermore, we find that electrochemistry is the governing mechanism even if a ferroelectric is placed between the metal and the oxide. Finally, we extend the concept of electroresistance to the tunnelling of superconducting quasiparticles, for which the switching effects are much stronger than for normal electrons. Besides providing crucial understanding, our results provide a basis for non-volatile Josephson memory devices.

Long-Range Propagation and Interference of d -wave Superconducting Pairs in Graphene

“…Those features are reminiscent of the conductance decrease/increase observed for ejV BIAS j < Δ in superconducting-normal-metal junctions depending on the interface transparency [31]. However, here they extend over a bias range δ exp that clearly exceeds the superconducting energy gap expected for moderately underdoped to optimally doped YBCO, which is reported in the range Δ YBCO ∼ 15-30 meV [32][33][34][35]. Furthermore, details such as the sharp zero-bias peak observed for some devices (see, e.g., B4D and E3D in the Supplemental Material [36]) are characteristic of junctions involving dwave superconductors, and appear when the d-wave nodes form a certain angle with respect to the junction interface [33,37,38].…”

Switchable Optically Active Schottky Barrier in La0.7Sr0.3MnO3/BaTiO3/ITO Ferroelectric Tunnel Junction

“…and multiferroic tunnel junctions, [6][7][8][9][10][11] in the improvement of photovoltaic devices for clean power generation, [12][13][14][15][16] and in the implementation of memristors for neuromorphic computing. [17][18][19][20] Most of these research relies on high quality thin film FEs, which benefitted from the great development of growth techniques in the last decades.…”

Resistive Switching and Redox Process at the BaTiO3/(La,Sr)MnO3 Multiferroic‐Type Interface

“…Very recently, the redox processes with oxygen exchange at interfaces have been put forward to explain TER effects. [26] In any capacitive structure with a dielectric barrier, the incomplete screening of the charges at the interfaces, will act on the electrostatic potential overall profile. [13,[27][28] As a result, the reversal of an applied electric field will generate two distinct barrier profiles for the transport of electrons, inducing the ER effect.…”

“…Very recently, the redox processes with oxygen exchange at interfaces have been put forward to explain TER effects. [ 26 ]…”