Physicists Find Structural Phase Transitions in 2-D Atomic Materials

Courtesy of Salvador Barraza-Lopez

FAYETTEVILLE, Ark. – An international team led by University of Arkansas physicists has discovered drastic changes in material properties occurring in a group of two-dimensional materials that are being investigated as candidates to power the next generation of opto-electronic devices.

The findings, published in the journal Physical Review Letters, reveal the rich properties of a new class of “phase-change” 2-D materials known as group-IV monochalcogenide monolayers and bilayers.

The U of A team consisted of Mehrshad Mehboudi, a doctoral student; Yurong Yang, a research assistant professor; Laurent Bellaiche, Distinguished Professor of physics; and assistant professors of physics Pradeep Kumar and Salvador Barraza-Lopez. Their collaborators were Benjamin Fregoso at the University of California-Berkeley, Wenjuan Zhu and Arend van der Zande, both at the University of Illinois; and Jaime Ferrer from Universidad de Oviedo in Spain.

“We are the first team to even realize the possibility of such two-dimensional structural transitions in 2-D atomic materials, and the first team to ever study the effect of such transitions on material properties,” Barraza-Lopez said.

The transition is the change from a rectangle to a square unit cell occurring near room temperature. As a result of the transition, optical properties, charge transport, and intrinsic dipole moments in the case of monolayers are shown to change in an abrupt manner.

“These changes in properties make these materials an exciting platform for novel optoelectronic applications, and they also uncover fundamental physics of structural phase transitions in reduced dimensions,” Barraza-Lopez said. “No such detailed analysis had been provided before this work.”

The research was carried out entirely on the Trestles supercomputer in the Arkansas High Performance Computing Center at the U of A.

Contacts

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