Above-room-temperature ferromagnetism in ultrathin van der Waals magnet

Two-dimensional (2D) magnetic van der Waals materials provide a powerful platform for studying fundamental physics of low-dimensional magnetism, engineering novel magnetic phases, and enabling ultrathin and highly tunable spintronic devices. To realize high quality and practical devices for such app...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2022-06
Main Authors: Chen, Hang, Shahidul Asif, Dolui, Kapildeb, Wang, Yang, Jeyson, Tamara Isaza, V M L Durga Prasad Goli, Whalen, Matthew, Wang, Xinhao, Chen, Zhijie, Zhang, Huiqin, Liu, Kai, Jariwala, Deep, Jungfleisch, M Benjamin, Chakraborty, Chitraleema, May, Andrew F, McGuire, Michael A, Nikolic, Branislav K, Xiao, John Q, Ku, Mark J H
Format: Article
Language:English
Subjects:
Curie temperature
Diamonds
Exfoliation
Ferromagnetism
Flakes
High temperature
Magnetism
Magnets
Monolayers
Robustness
Room temperature
Single crystals
Temperature
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Two-dimensional (2D) magnetic van der Waals materials provide a powerful platform for studying fundamental physics of low-dimensional magnetism, engineering novel magnetic phases, and enabling ultrathin and highly tunable spintronic devices. To realize high quality and practical devices for such applications, there is a critical need for robust 2D magnets with ordering temperatures above room temperature that can be created via exfoliation. Here the study of exfoliated flakes of cobalt substituted Fe5GeTe2 (CFGT) exhibiting magnetism above room temperature is reported. Via quantum magnetic imaging with nitrogen-vacancy centers in diamond, ferromagnetism at room temperature was observed in CFGT flakes as thin as 16 nm. This corresponds to one of the thinnest room-temperature 2D magnet flakes exfoliated from robust single crystals, reaching a thickness relevant to practical spintronic applications. The Curie temperature Tc of CFGT ranges from 310 K in the thinnest flake studied to 328 K in the bulk. To investigate the prospect of high-temperature monolayer ferromagnetism, Monte Carlo calculations were performed which predicted a high value of Tc ~270 K in CFGT monolayers. Pathways towards further enhancing monolayer Tc are discussed. These results support CFGT as a promising platform to realize high-quality room-temperature 2D magnet devices.
ISSN:2331-8422
DOI:10.48550/arxiv.2206.07027