Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal

Structural-property relationship, the connection between materials' structures and their properties, is central to the materials research. Especially at reduced dimensions, novel structural motifs often generate unique physical properties.Motivated by a recent work reporting a novel half auxeti...

Full description

Saved in:
Bibliographic Details
Main Authors: Gao, Zhen, Wang, Qianqian, Wu, Weikang, Tian, Zhixue, Liu, Ying, Ma, Fengxian, Jiao, Yalong, Yang, Shengyuan A.
Other Authors: School of Physical and Mathematical Sciences
Format: Article
Language:English
Published: 2023
Subjects:
Online Access:https://hdl.handle.net/10356/164301
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
Language: English
id sg-ntu-dr.10356-164301
record_format dspace
spelling sg-ntu-dr.10356-1643012023-02-28T20:09:21Z Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal Gao, Zhen Wang, Qianqian Wu, Weikang Tian, Zhixue Liu, Ying Ma, Fengxian Jiao, Yalong Yang, Shengyuan A. School of Physical and Mathematical Sciences Science::Physics Auxetics Dirac Point Structural-property relationship, the connection between materials' structures and their properties, is central to the materials research. Especially at reduced dimensions, novel structural motifs often generate unique physical properties.Motivated by a recent work reporting a novel half auxetic effect in monolayer PdB4 with a hypercoordinated structure, here, we extensively explore similar 2D transition metal boride structures MB4 with M covering 3d and 4d elements.Our investigation screens out one stable candidate, the monolayer RhB4. We find that monolayer RhB4 also shows half auxeticity, i.e., the material always expands in a lateral in-plane direction in response to an applied strain in the other direction, regardless of whether the strain is positive or negative.We show that this special mechanical character is intimately tied to the hypercoordinated structure with the M\c{opyright}B8 structural motif. Furthermore, regarding electronic properties, monolayer RhB4 is found to be the first example of an almost ideal 2D spin-orbit Dirac point semimetal.The low-energy band structure is clean, with a pair of fourfold degenerate Dirac points robust under spin-orbit coupling located close to the Fermi level. These Dirac points are enforced by the nonsymmorphic space group symmetry which is also determined by the lattice structure. Our work deepens the fundamental understanding of structural-property relationship in reduced dimensions. The half auxeticity and the spin-orbit Dirac points will make monolayer RhB4 a promising platform for nanomechanics and nanoelectronics applications. Ministry of Education (MOE) Published version This work is supported by the National Natural Science Foundation of China (Grants No. 11847017 and No. 11904077), Science Foundation of Hebei Normal University (Grant No. L2019B09), financial support program from Hebei Province (Grant No. E2019050018), Alexander von Humboldt-Foundation, and Singapore MOE AcRF Tier 2 (Grant No. MOE2019-T2-1-001). 2023-01-16T00:48:12Z 2023-01-16T00:48:12Z 2021 Journal Article Gao, Z., Wang, Q., Wu, W., Tian, Z., Liu, Y., Ma, F., Jiao, Y. & Yang, S. A. (2021). Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal. Physical Review B, 104(24), 245423-1-245423-6. https://dx.doi.org/10.1103/PhysRevB.104.245423 1098-0121 https://hdl.handle.net/10356/164301 10.1103/PhysRevB.104.245423 2-s2.0-85122038899 24 104 245423-1 245423-6 en MOE2019-T2-1-001 Physical Review B © 2021 American Physical Society. All rights reserved. This paper was published in Physical Review B and is made available with permission of American Physical Society. application/pdf
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic Science::Physics
Auxetics
Dirac Point
spellingShingle Science::Physics
Auxetics
Dirac Point
Gao, Zhen
Wang, Qianqian
Wu, Weikang
Tian, Zhixue
Liu, Ying
Ma, Fengxian
Jiao, Yalong
Yang, Shengyuan A.
Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
description Structural-property relationship, the connection between materials' structures and their properties, is central to the materials research. Especially at reduced dimensions, novel structural motifs often generate unique physical properties.Motivated by a recent work reporting a novel half auxetic effect in monolayer PdB4 with a hypercoordinated structure, here, we extensively explore similar 2D transition metal boride structures MB4 with M covering 3d and 4d elements.Our investigation screens out one stable candidate, the monolayer RhB4. We find that monolayer RhB4 also shows half auxeticity, i.e., the material always expands in a lateral in-plane direction in response to an applied strain in the other direction, regardless of whether the strain is positive or negative.We show that this special mechanical character is intimately tied to the hypercoordinated structure with the M\c{opyright}B8 structural motif. Furthermore, regarding electronic properties, monolayer RhB4 is found to be the first example of an almost ideal 2D spin-orbit Dirac point semimetal.The low-energy band structure is clean, with a pair of fourfold degenerate Dirac points robust under spin-orbit coupling located close to the Fermi level. These Dirac points are enforced by the nonsymmorphic space group symmetry which is also determined by the lattice structure. Our work deepens the fundamental understanding of structural-property relationship in reduced dimensions. The half auxeticity and the spin-orbit Dirac points will make monolayer RhB4 a promising platform for nanomechanics and nanoelectronics applications.
author2 School of Physical and Mathematical Sciences
author_facet School of Physical and Mathematical Sciences
Gao, Zhen
Wang, Qianqian
Wu, Weikang
Tian, Zhixue
Liu, Ying
Ma, Fengxian
Jiao, Yalong
Yang, Shengyuan A.
format Article
author Gao, Zhen
Wang, Qianqian
Wu, Weikang
Tian, Zhixue
Liu, Ying
Ma, Fengxian
Jiao, Yalong
Yang, Shengyuan A.
author_sort Gao, Zhen
title Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
title_short Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
title_full Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
title_fullStr Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
title_full_unstemmed Monolayer RhB4: half-auxeticity and almost ideal spin-orbit Dirac point semimetal
title_sort monolayer rhb4: half-auxeticity and almost ideal spin-orbit dirac point semimetal
publishDate 2023
url https://hdl.handle.net/10356/164301
_version_ 1759853826026766336