NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Emergent Magnetic State in (111)-Oriented Quasi-Two-Dimensional Spinel Oxides
Published
Author(s)
Xiaoran Liu, Sobhit Singh, Brian Kirby, Zhicheng Zhong, Yanwei Cao, Banabir Pal, Mikhail Kareev, Srimanta Middey, John W. Freeland, Padraic Shafer, Elke Arenholz, David Vanderbilt, Jak Chakhalian
Abstract
We report on the emergent magnetic state of (111)-oriented CoCr2O4 ultrathin films sandwiched by Al2O3 in the quantum confined geometry. At the two-dimensional crossover, polarized neutron reflectometry reveals an anomalous enhancement of the total magnetization compared to the bulk value. Synchrotron x-ray magnetic circular dichroism (XMCD) demonstrates the appearance of long-range ferromagnetic ordering of spins on both Co and Cr sublattices. Brillouin function analyses further corroborates that the observed phenomena are due to the strongly altered magnetic frustration, manifested by the onset of a Yafet-Kittel type ordering as the new ground state in the ultrathin limit, which is unattainable in the bulk.
Liu, X.
, Singh, S.
, Kirby, B.
, Zhong, Z.
, Cao, Y.
, Pal, B.
, Kareev, M.
, Middey, S.
, Freeland, J.
, Shafer, P.
, Arenholz, E.
, Vanderbilt, D.
and Chakhalian, J.
(2019),
Emergent Magnetic State in (111)-Oriented Quasi-Two-Dimensional Spinel Oxides, Nano Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=928221
(Accessed October 13, 2025)