Superconductivity-induced Magnetic Modulation in a Ferromagnet Through an Insulator in LaCaMnO3\SrTiO3\YBa2Cu3O7-{\delta} Hybrid Heterostructures

TL;DR

This study reveals that superconductivity in YBa2Cu3O7-{ extdelta} can suppress ferromagnetic order in LaCaMnO3 through an insulating layer, demonstrating a novel magnetic modulation effect in heterostructures.

Contribution

It provides the first experimental evidence of superconductivity-induced magnetic suppression across an insulator in a ferromagnet-superconductor heterostructure.

Findings

Observation of a magnetic dead layer in LaCaMnO3 below the superconductor's transition temperature.

The magnetic dead layer thickness increases as the insulating layer becomes thinner.

Superconducting order parameter tunneling induces magnetization modulation in the ferromagnet.

Abstract

Coexistence of ferromagnetic and superconducting orders and their interplay in ferromagnet-superconductor heterostructures is a topic of intense research. While it is well known that proximity of a ferromagnet suppresses superconducting order in the superconductor, there exist few studies indicating the proximity of a superconductor suppressing ferromagnetic order in a ferromagnet. Here we demonstrate a rare observation of the suppression of ferromagnetic order in a LaCaMnO3 layer separated from a YBa2Cu3O7-{\delta} layer by a thin insulator (SrTiO3). Polarized neutron reflectivity measurements on LaCaMnO3\SrTiO3\YBa2Cu3O7-{\delta} trilayer deposited on [001] SrTiO3 single crystal substrates shows the emergence of a thin magnetic dead layer in LaCaMnO3 adjacent to the insulating layer below its superconducting transition temperature of YBa2Cu3O7-{\delta}. Further, the magnetic dead layer grows in thickness when the insulating layer is made thinner. This indicates a possible tunneling of the superconducting order-parameter through the insulating SrTiO3 inducing modulation of magnetization in LaCaMnO3.