Exchange Frustration and Topological Magnetism in Electrostatically Doped SrRuO3

TL;DR

This study demonstrates that electrostatic doping via ferroelectric polarization can control exchange frustration and induce topological magnetic textures in SrRuO3, enabling engineering of complex magnetic phases.

Contribution

It introduces a method to manipulate exchange interactions and topological magnetism in SrRuO3 using electrostatic doping and ferroelectric polarization.

Findings

Electrostatic hole doping drives SrRuO3 into frustrated magnetic regimes.

Polarization-induced charge depletion modulates exchange couplings at interfaces.

Exchange frustration stabilizes diverse magnetic phases including skyrmions and merons.

Abstract

Magnetism in transition-metal systems emerges from exchange interactions that depend sensitively on carrier density. Yet leveraging this sensitivity to deliberately engineer exchange frustration and associated topological spin textures remains largely unexplored. Here, combining first-principles calculations with atomistic Monte Carlo simulations, we demonstrate that ferroelectric polarization enables electrostatic control of exchange frustration in the itinerant ferromagnet SrRuO3. We show that electrostatic hole doping renormalizes competing exchange interactions, driving SrRuO3 away from its bulk ferromagnetic ground state toward frustrated regimes, whereas electron doping largely preserves ferromagnetism. At BaTiO3/SrRuO3 interfaces, polarization-induced charge depletion modulates layer dependent exchange couplings, enhancing competition among J1, J2 and J3. The resulting exchange frustration stabilizes a sequence of magnetic phases as a function of thickness and applied magnetic field, including stripe and spiral states, topological meron and bimeron textures, and diverse skyrmionic objects. A minimal spin model identifies exchange frustration as the primary control parameter governing these crossovers, with magnetic anisotropy, Dzyaloshinskii-Moriya interaction, and external field selecting the emergent topology. Our results establish electrostatic doping as a route to engineer frustrated and topological magnetism in itinerant oxide metals.