Relaxation electrodynamics of superinsulators

Abstract

Superinsulators offer a unique laboratory realizing strong interaction phenomena like confinement and asymptotic freedom in quantum materials. Recent experiments evidenced that superinsulators are the mirror-twins of superconductors with reversed electric and magnetic field effects. Cooper pairs and Cooper holes in the superinsulator are confined into neutral electric pions by electric strings, with the Cooper pairs playing the role of quarks. Here we report the non-equilibrium relaxation of the electric pions in superinsulating films. We find that the time delay $$t_{\mathrm {sh}}$$ t sh of the current passage in the superinsulator is related to the applied voltage V via the power law, $$t_{\mathrm {sh}}\propto (V-V_{\mathrm p})^{-\mu }$$ t sh ∝ ( V - V p ) - μ , where $$V_{\mathrm p}$$ V p is the effective threshold voltage. Two distinct critical exponents, $$\mu =1/2$$ μ = 1 / 2 and $$\mu =3/4$$ μ = 3 / 4 , correspond to jumps from the electric Meissner state to the mixed state and to the superinsulating resistive state with broken charge confinement, respectively. The $$\mu =1/2$$ μ = 1 / 2 value establishes a direct experimental evidence for the electric strings’ linear potential confining the charges of opposite signs in the electric Meissner state and effectively rules out disorder-induced localization as a mechanism for superinsulation. We further report the memory effects and their corresponding dynamic critical exponents arising upon the sudden reversal of the applied voltage. Our observations open routes for exploring fundamental strong interaction charge confinement via desktop experiments.

Gauge Theories of Josephson Junction Arrays: Why Disorder Is Irrelevant for the Electric Response of Disordered Superconducting Films

“…Superinsulators [17,[36][37][38][39], with their divergent electrical resistance, have been experimentally detected in InO [40], TiN [36], NbTiN [41], and NbSi [42]. A recent measurement of the dynamic response of superinsulators confirmed that the potential holding together ± charges is indeed linear [43].…”

Topological Gauge Theory of Josephson Junction Arrays: The Discovery of Superinsulation

“…They were first theoretically predicted in [5], while the final form of the theory describing this new state of matter was established in [7]. Superinsulators have been experimentally detected [8][9][10][11][12][13][14] in thin superconducting films, which, close to the SIT, have an emergent granularity and behave as a self-organized JJA.…”

Topological Gauge Theory of Josephson Junction Arrays: The Discovery of Superinsulation

“…They were first theoretically predicted in [5], while the final form of the theory describing this new state of matter was established in [7]. Superinsulators have, than, been experimentally found in [8][9][10][11][12][13][14] in thin superconducting films which, close to the SIT, have an emergent granularity and behave as a self organized JJA.…”