Exchange Field-Mediated Magnetoresistance in the Correlated Insulator Phase of Be Films

Abstract

We present a study of the proximity effect between a ferromagnet and a paramagnetic metal of varying disorder. Thin beryllium films are deposited onto a 5 nm-thick layer of the ferromagnetic insulator EuS. This bilayer arrangement induces an exchange field, $H_{ex}$, of a few tesla in low resistance Be films with sheet resistance $R\ll R_Q$, where $R_Q=h/e^2$ is the quantum resistance. We show that $H_{ex}$ survives in very high resistance films and, in fact, appears to be relatively insensitive to the Be disorder. We exploit this fact to produce a giant low-field magnetoresistance in the correlated insulator phase of Be films with $R\gg R_Q$.

To be published in Physical Review Letters

References in corpus (5)

• Inverse proximity effect in superconductor-ferromagnet bilayer structures
• Josephson tunnel junctions with strong ferromagnetic interlayer
• Spin-Resolved Tunneling Studies of the Exchange Field in EuS/Al Bilayers
• Unconventional proximity effect and inverse spin-switch behavior in a model manganite-cuprate-manganite trilayer system
• Measurement of Conduction Electron Polarization Via the Pairing Resonance

Cited by in corpus (1)

• Majorana fermions in semiconductor nanostructures with two wires connected through ring