Tunable 2D Group-III Metal Alloys

Siavash Rajabpour; Alexander Vera; Wen He; Benjamin N Katz; Roland J Koch; Margaux Lassaunière; Xuegang Chen; Cequn Li; Katharina Nisi; Hesham El-Sherif; Maxwell T Wetherington; Chengye Dong; Aaron Bostwick; Chris Jozwiak; Adri C T van Duin; Nabil Bassim; Jun Zhu; Gwo-Ching Wang; Ursula Wurstbauer; Eli Rotenberg; Vincent Crespi; Su Ying Quek; Joshua A Robinson

doi:10.1002/adma.202104265

Tunable 2D Group-III Metal Alloys

Adv Mater. 2021 Nov;33(44):e2104265. doi: 10.1002/adma.202104265. Epub 2021 Sep 4.

Authors

Siavash Rajabpour^{1

2}, Alexander Vera^{2

3}, Wen He^{4

5}, Benjamin N Katz^{2

6}, Roland J Koch⁷, Margaux Lassaunière^{8

9}, Xuegang Chen¹⁰, Cequn Li^{2

6}, Katharina Nisi^{8

11}, Hesham El-Sherif¹², Maxwell T Wetherington^{3

13}, Chengye Dong^{2

14}, Aaron Bostwick⁷, Chris Jozwiak⁷, Adri C T van Duin^{1

2

3

13

14

15

16

17}, Nabil Bassim^{12

18}, Jun Zhu^{2

6}, Gwo-Ching Wang¹⁰, Ursula Wurstbauer^{8

9}, Eli Rotenberg⁷, Vincent Crespi^{2

3

6

13

14

16}, Su Ying Quek^{4

5

19

20}, Joshua A Robinson^{2

3

13

14}

Affiliations

¹ Department of Chemical Engineering, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
² Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
³ Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
⁴ Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive, Singapore, 117575, Singapore.
⁵ Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore, 117546, Singapore.
⁶ Department of Physics, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
⁷ Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
⁸ Institute of Physics, University of Münster, Münster, 48149, Germany.
⁹ Center for Soft Nanoscience, University of Münster, Münster, 48149, Germany.
¹⁰ Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
¹¹ Physics Department, Technical University of Munich, Garching, 85748, Germany.
¹² Department of Materials Science and Engineering, McMaster University, Hamilton, Ontario, L8S 4L8, Canada.
¹³ Materials Research Institute, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
¹⁴ 2-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
¹⁵ Department of Mechanical Engineering, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
¹⁶ Department of Chemistry, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
¹⁷ Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Berkeley, PA, 16802, USA.
¹⁸ Canadian Centre for Electron Microscopy, Hamilton, Ontario, L8S 4L8, Canada.
¹⁹ Department of Physics, National University of Singapore, Singapore, 117551, Singapore.
²⁰ NUS Graduate School Integrative Sciences and Engineering Programme, National University of Singapore, Singapore, 117456, Singapore.

PMID: 34480500
DOI: 10.1002/adma.202104265

Abstract

Chemically stable quantum-confined 2D metals are of interest in next-generation nanoscale quantum devices. Bottom-up design and synthesis of such metals could enable the creation of materials with tailored, on-demand, electronic and optical properties for applications that utilize tunable plasmonic coupling, optical nonlinearity, epsilon-near-zero behavior, or wavelength-specific light trapping. In this work, it is demonstrated that the electronic, superconducting, and optical properties of air-stable 2D metals can be controllably tuned by the formation of alloys. Environmentally robust large-area 2D-In_x Ga_1- _x alloys are synthesized byConfinement Heteroepitaxy (CHet). Near-complete solid solubility is achieved with no evidence of phase segregation, and the composition is tunable over the full range of x by changing the relative elemental composition of the precursor. The optical and electronic properties directly correlate with alloy composition, wherein the dielectric function, band structure, superconductivity, and charge transfer from the metal to graphene are all controlled by the indium/gallium ratio in the 2D metal layer.

Keywords: 2D materials; optical properties; superconductivity; tunable properties.

Abstract

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