Researchers Show Temperature Can Dramatically Affect Behavior of 2-D Materials

A tin selenide monochalcogenide monolayer at room temperature.
Courtesy of Edmund O. Harriss

A tin selenide monochalcogenide monolayer at room temperature.

FAYETTEVILLE, Ark. – New research at the University of Arkansas shows that temperature can be used to dramatically alter the behavior of two-dimensional materials that are being investigated as candidates to power the next generation of electronic devices.

The research revealed black phosphorous and monochalcogenide monolayers act differently than any other known 2-D materials at any given temperature because there are four ways to create their atomistic arrangement, and these four arrangements compete and lead to disorder, said Salvador Barraza-Lopez, an assistant professor of physics at the University of Arkansas.

“Remarkably, nobody had found that some of these two-dimensional materials become disordered at a room temperature and well before they melt,” Barraza-Lopez said. “At the transition temperature the unit cell transforms from a rectangle onto a square and all material properties change.”

An international research team led by Barraza-Lopez and Pradeep Kumar, assistant professor of physics at the U of A, published its findings in Nano Letters, a journal of the American Chemical Society.

The black phosphorous and monochalcogenide monolayers become disordered at a finite temperature, Barraza-Lopez said.

“At that moment, the structure transforms from a rectangle to a square and its behavior also changes,” he said. 

Having access to the Trestles supercomputer at the Arkansas High Performance Computing Center was crucial to the study, Barraza-Lopez said.

Barraza-Lopez and Mehrshad Mehboudi ran multiple calculations on Trestles for about three weeks each and without interruption. Mehboudi is a doctoral student in the university’s interdisciplinary microelectronics-photonics graduate program.

“There is no way we could have achieved these results in the timeframe we did without Trestles,” Barraza-Lopez said.

The work benefited from contributions by Hugh Churchill, assistant professor of physics at the U of A, and Edmund Harriss, a clinical assistant professor in the U of A Department of Mathematical Sciences.

Additional contributors were Arend van der Zande and Wenjuan Zhu of the University of Illinois, Alejandro A. Pacheco-Sanjuan of the Universidad Technica Federico Santa Maria in Chile, and Alex M. Dorio, an undergraduate at Oklahoma State University who participated in a Research for Undergraduates experience at the U of A last summer. 

Contacts

Salvador Barraza-Lopez, assistant professor
Department of Physics
479-575-5933, sbarraza@uark.edu

Chris Branam, research communications writer/editor
University Relations
479-575-4737, cwbranam@uark.edu


Headlines

Tyson Family Adds $1 Million Gift During Dedication of Iconic Research Building

John Tyson, chairman of Tyson Foods, announced a new gift during dedication ceremonies for the new Don Tyson Center for Agricultural Sciences.

U of A Faculty, Staff, Students Present Research at National Association Meeting

University of Arkansas faculty and staff members and graduate students took part recently in the American Association for Adult and Continuing Education annual conference in Memphis.

Exercise Science Doctoral Students to Talk About Their Research Friday

Wesley Haynie and Hyun-Gyu "Sean" Suh, doctoral students in exercise science, will give research presentations from 3 to 4 p.m. Friday, Nov. 17, in HPER 311.

MyDocs, Gizmo, SharePoint and Other Services Affected by Weekend Maintenance

On Saturday morning, MyDocs, Gizmo, SharePoint and other systems relying on the SQL server will be briefly interrupted during routine Windows Server maintenance.

Participants Needed for Study Examining Effect of Diet on Health in Families

The Department of Food Science is recruiting families, defined as at least one parent/guardian, with at least one child between the ages of 6-12 years to participate in a nutrition study.

Newswire Daily