Growth and characterisation studies of Eu3O4 thin films grown on Si/SiO2 and graphene

DOI: 10.3390/nano11061598

Authors: Razan O. M. Aboljadayel (University of Cambridge; Diamond Light Source) , Adrian Ionescu (University of Cambridge) , Oliver J. Burton (University of Cambridge) , Gleb Cheglakov (University of Cambridge) , Stephan Hofmann (University of Cambridge) , Crispin H. W. Barnes (University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nanomaterials , VOL 11

State: Published (Approved)
Published: June 2021

Abstract: We report the growth, structural and magnetic properties of the less studied Eu-oxide phase, Eu3 O4 , thin films grown on a Si/SiO2 substrate and Si/SiO2 /graphene using molecular beam epitaxy. The X-ray diffraction scans show that highly textured crystalline Eu3 O4 (001) films are grown on both substrates, whereas the film deposited on graphene has a better crystallinity than that grown on the Si/SiO2 substrate. The SQUID measurements show that both films have a Curie temperature of ∼5.5±0.1 K, with a magnetic moment of ∼320 emu/cm3 at 2 K. The mixed valence of the Eu cations has been confirmed by the qualitative analysis of the depth-profile X-ray photoelectron spectroscopy measurements with the Eu2+ :Eu3+ ratio of 28:72 . However, surprisingly, our films show no metamagnetic behaviour as reported for the bulk and powder form. Furthermore, the microscopic optical images and Raman measurements show that the graphene underlayer remains largely intact after the growth of the Eu3 O4 thin films.

Journal Keywords: Eu3O4; graphene; thin film; heterostructure; metamagnetism; XPS

Subject Areas: Materials, Physics


Technical Areas:

Added On: 05/07/2021 14:12

Documents:
nanomaterials-11-01598-v2.pdf

Discipline Tags:

Surfaces Physics Magnetism Materials Science interfaces and thin films

Technical Tags: