In Situ Control of Diamagnetism by Electric Current in Ca3(Ru1−xTix

Abstract

Non-equilibrium steady state (NESS) conditions induced by DC current can alter the physical properties of strongly correlated electron systems (SCES). In this regard, it was recently shown that DC current can trigger novel electronic states, such as current-induced diamagnetism, which cannot be realized in equilibrium conditions. However, reversible control of diamagnetism has not been achieved yet. Here, we demonstrate reversible in situ control between a Mott insulating state and a diamagnetic semimetal-like state by DC current in the Tisubstituted bilayer ruthenate Ca 3 (Ru 1−x Ti x ) 2 O 7 (x = 0.5%). By performing simultaneous magnetic and resistive measurements, we map out the temperature vs current-density phase diagram in the NESS of this material. The present results open up the possibility of creating novel electronic states in a variety of SCES under DC current.

Emergence of a metallic metastable phase induced by electrical current in Ca2RuO4

“…Indeed, a new crystal structure supposing to be the manifestation of a new semi-metallic state was reported by a measurement protocol completely different from the one presented in this work 27 , while alternating insulating and metallic regions arranged in stripes patterns at the M-I phase boundary were observed in the regime of controlled constant current flow 26 . Moreover, it is now accepted that dc current biasing can be used to control the magnetic properties of the system, since, under current flow, strong diamagnetism is induced in pure Ca-214 and in Ca 3 Ru 1−x Ti x O 7 2, 28 and AFM order is suppressed in pure Ca-214 27,28 .…”

Raman scattering from current-stabilized nonequilibrium phases in Ca2RuO4

“…In the future, it will be interesting to extend our Raman experiments to nonzero momentum transfer by using intermediate-energy resonant inelastic x-ray scattering at the Ru L edges 40 . It would be also beneficial to perform scattering experiments with applied electrical current on ruthenates and other compounds that are less insulating in nature, such as the Ti-substituted bilayer ruthenate Ca 3 (Ru 1−x Ti x ) 2 O 7 41 , as this would allow to explore more in detail the low current regimes.…”

Spatial inhomogeneity and the metal-insulator transition in Ca3(Ru1−xTix)2Lechermann1, Han2, Millis3 2020Phys. Rev. Research5000View full textAdd to dashboardCite

“…Other effects such as hopping blocking or average structural modification via a change of lattice parameters furthermore support the insulating tendencies with doping, but appear not decisive. The site-selective physics reported here may also be relevant for an understanding and modeling of recently discovered current-induced diamagnetism [39] in Ti-doped Ca 3 Ru 2 O 7 . Describing the transport scenario from a possibly current-induced (partial-)gap closing and/or the coexistence of diamagnetism with persisting (local) magnetic order could rely on the important interplay of electronic correlation and spatial inhomogeneity.…”