Title: Strain-Induced Spatially Resolved Charge Transport in 2H-MoTe ₂

Abstract

Strain engineering offers unique control to manipulate the electronic band structure of two-dimensional (2D) materials, resulting in an effective and continuous tuning of the physical properties. Ad hoc straining of 2D materials has demonstrated state of the art photonic devices including efficient photodetectors at telecommunication frequencies, enhancedmobility transistors, and on-chip single photon sources, for example. However, in order to gain insights into the underlying mechanism required to enhance the performance of the next-generation devices with strain(op)tronics, it is imperative to understand the nano- and microscopic properties as a function of a strong nonhomogeneous strain. Here, we study the strain-induced variation of local conductivity of a few-layer transition metal dichalcogenide using conductive atomic force microscopy. We report a strain characterization technique by capturing the electrical conductivity variations induced by local strain originating from surface topography at the nanoscale, which allows overcoming limitations of existing optical spectroscopy techniques. We show that the conductivity variations parallel the strain deviations across the geometry predicted by molecular dynamics simulation. These results substantiate a variation of the effective mass and surface charge density by 0.026me and 0.03e for every percent of uniaxial strain, respectively, derived using band structure calculation based on the first-principles density functional theory.more » Furthermore, we demonstrate modulation of the effective Schottky barrier height by quantifying its alteration originating from a gradual reduction of the conduction band minima as a function of tensile strain. Such spatially textured electronic behavior via surface topography-induced strain variations in atomistic-layered materials at the nanoscale opens up exciting opportunities to control fundamental material properties and offers a myriad of design and functional device possibilities, such as for electronics, nanophotonics, flextronics, or smart cloths.« less

Authors:

Maiti, Rishi  ^[1];

• Search DOE PAGES for author "Maiti, Rishi"
• Search DOE PAGES for ORCID "0000-0002-9236-5124"

Saadi, Md Abid Shahriar Rahman ^[2]; Amin, Rubab  ^[1];

• Search DOE PAGES for author "Amin, Rubab"
• Search DOE PAGES for ORCID "0000-0002-4783-3080"

Ozcelik, Veli Ongun  ^[3];

• Search DOE PAGES for author "Ozcelik, Veli Ongun"
• Search DOE PAGES for ORCID "0000-0003-0645-7231"

Uluutku, Berkin ^[2]; Patil, Chandraman ^[1]; Suer, Can ^[1]; Solares, Santiago ^[2]; Sorger, Volker J.  ^[1]

• Search DOE PAGES for author "Sorger, Volker J."
• Search DOE PAGES for ORCID "0000-0002-5152-4766"

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+ Show Author Affiliations

1. Department of Electrical and Computer Engineering, George Washington University, Washington, District of Columbia 20052, United States
2. Department of Mechanical and Aerospace Engineering, George Washington University, Washington, District of Columbia 20052, United States
3. Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States, Materials Science and Engineering Program, University of California San Diego, La Jolla, California 92093, United States

Publication Date:

Thu Aug 26 00:00:00 EDT 2021

Research Org.:

George Washington Univ., Washington, DC (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1819988

Alternate Identifier(s):

OSTI ID: 1822843

Grant/Contract Number:  

SC0018041

Resource Type:

Published Article

Journal Name:

ACS Applied Electronic Materials

Additional Journal Information:

Journal Name: ACS Applied Electronic Materials Journal Volume: 3 Journal Issue: 9; Journal ID: ISSN 2637-6113

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; two-dimensional materials; strain engineering; conductive atomic force microscopy; density of states; Schottky barrier; chemical structure; quantum mechanics; electrical conductivity; layers; materials