Title: Phonon Polariton-assisted Infrared Nanoimaging of Local Strain in Hexagonal Boron Nitride

Abstract

Strain plays an important role in condensed matter physics and materials science because it can strongly modify the mechanical, electrical, and optical properties of a material and even induce a structural phase transition. Strain effects are especially interesting in atomically thin two-dimensional (2D) materials, where unusually large strain can be achieved without breaking them. Measuring the strain distribution in 2D materials at the nanometer scale is therefore greatly important but is extremely challenging experimentally. Here, we use near-field infrared nanoscopy to demonstrate phonon polariton-assisted mapping and quantitative analysis of strain in atomically thin polar crystals of hexagonal boron nitride (hBN) at the nanoscale. A local strain as low as 0.01% can be detected using this method with ~20 nm spatial resolution. Such ultrasensitive nanoscale strain imaging and analysis technique opens up opportunities for exploring unique local strain structures and strain-related physics in 2D materials. In addition, experimental evidence for local strain-induced phonon polariton reflection is also provided, which offers a new approach to manipulate light at deep subwavelength scales for nanophotonic devices.

Authors:

Lyu, Bosai  ^[1];

• Search DOE PAGES for author "Lyu, Bosai"
• Search DOE PAGES for ORCID "0000-0001-8044-5509"

Li, Hongyuan  ^[1];

• Search DOE PAGES for author "Li, Hongyuan"
• Search DOE PAGES for ORCID "0000-0001-9119-5592"

Jiang, Lili ^[2]; Shan, Wanfei ^[1]; Hu, Cheng ^[1]; Deng, Aolin ^[1]; Ying, Zhe ^[1]; Wang, Lele ^[1]; Zhang, Yiran ^[1]; Bechtel, Hans A. ^[3]; Martin, Michael C. ^[3]; Taniguchi, Takashi ^[4]; Watanabe, Kenji ^[4]; Luo, Weidong ^[5]; Wang, Feng ^[6]; Shi, Zhiwen  ^[1]

• Search DOE PAGES for author "Shi, Zhiwen"
• Search DOE PAGES for ORCID "0000-0002-3928-2960"

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+ Show Author Affiliations

1. Shanghai Jiao Tong Univ. (China). Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy; Collaborative Innovation Center of Advanced Microstructures, Nanjing (China)
2. Univ. of California, Berkeley, CA (United States). Dept. of Physics
3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
4. National Institute for Materials Science, Namiki, Tsukuba (Japan)
5. Shanghai Jiao Tong Univ. (China). Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy; Collaborative Innovation Center of Advanced Microstructures, Nanjing (China); Shanghai Jiao Tong Univ. (China). Institute of Natural Sciences
6. Univ. of California, Berkeley, CA (United States). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Div.; Univ. of California, Berkeley, and Lawrence Berkeley National Laboratory, CA (United States). Kavli Energy NanoSciences Inst.

Publication Date:

Tue Feb 19 00:00:00 EST 2019

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22), Scientific User Facilities Division (SC-22.3 )

OSTI Identifier:

1526580

Grant/Contract Number:  

AC02-05CH11231

Resource Type:

Accepted Manuscript

Journal Name:

Nano Letters

Additional Journal Information:

Journal Volume: 19; Journal Issue: 3; Journal ID: ISSN 1530-6984

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE