Plechinger, Gerd and Castellanos-Gomez, Andres and Buscema, Michele and van der Zant, Herre S. J. and Steele, Gary A. and Kuc, Agnieszka and Heine, Thomas and Schueller, Christian and Korn, Tobias (2015) Control of biaxial strain in single-layer molybdenite using local thermal expansion of the substrate. 2D MATERIALS, 2 (1): 015006. ISSN 2053-1583,
Full text not available from this repository. (Request a copy)Abstract
Single-layer MoS2 is a direct-gap semiconductor whose electronic band structure strongly depends on the strain applied to its crystal lattice. While uniaxial strain can be easily applied in a controlled way, e.g., by bending of a flexible substrate with the atomically thin MoS2 layer on top, experimental realization of biaxial strain is more challenging. Here, we exploit the large mismatch between the thermal expansion coefficients of MoS2 and a silicone-based substrate to apply a controllable biaxial tensile strain by heating the substrate with a focused laser. The effect of this biaxial strain is directly observable in optical spectroscopy as a redshift of the MoS2 photoluminescence. We also demonstrate the potential of this method to engineer more complex strain patterns by employing highly absorptive features on the substrate to achieve non-uniform heat profiles. By comparison of the observed redshift to strain-dependent band structure calculations, we estimate the biaxial strain applied by the silicone-based substrate to be up to 0.2%, corresponding to a band gap modulation of 105 meV per percentage of biaxial tensile strain.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | ELECTRONIC-PROPERTIES; ELASTIC PROPERTIES; MONOLAYER MOS2; PHOTOLUMINESCENCE; ENERGY; single-layer molybdenum disulfide; atomically thin crystal; strain engineering; bandstructure; biaxial strain |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Experimental and Applied Physics > Chair Professor Lupton > Group Christian Schüller |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 24 Jul 2019 08:00 |
| Last Modified: | 24 Jul 2019 08:00 |
| URI: | https://pred.uni-regensburg.de/id/eprint/5828 |
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