Modulating antiferromagnetic La₀.₃₅Sr₀.₆₅ MnO₃ via low-voltage pulsing across a ferroelectric copolymer gate dielectric

Abstract

Electric-field-based modulation is a promising way for realizing ultrafast and high-density antiferromagnetic spintronics. Here, we investigate a low-voltage pulse modulation of antiferromagnetic La1-xSrxMnO₃ ( x =0.65 ) (AF-LSMO) thin films. Positive voltage pulses can increase the resistance at low temperatures, which is ascribed to the oxygen vacancies induced by positive voltage pulses. This effect is supported by X-ray photoelectron spectroscopy (XPS) results. Using low-voltage pulses, we demonstrate exchange bias modulation in ferromagnetic La₀.₇Sr₀.₃MnO₃ (FM-LSMO)/AF-LSMO bilayer structure. Temperature-dependent resistance, exchange bias field and coercivity all show voltage-polarity dependence. While positive pulses can induce significant changes in the AF-LSMO, negative pulsing has little impact and is consistent with oxygen vacancy related process observed in various electrochemical reaction systems. Our findings can find potential for exploring electric-field modification of antiferromagnetic spintronics.