Publications by Year: 2023

2023

Quan, J. ; Chen, G. ; Linhart, L. ; Liu, Z. ; Taniguchi, T. ; Watanabe, K. ; Libisch, F. ; Huang, R. ; Li, X. Quantifying Strain in Moiré Superlattice. Nano Letters 23, 11510 - 11516. Publisher's Version Abstract

In twisted van der Waals (vdW) bilayers, intrinsic strain associated with the moiré superlattice and unintentionally introduced uniaxial strain may be present simultaneously. Both strains are able to lift the degeneracy of the E2g phonon modes in Raman spectra. Because of the different rotation symmetry of the two types of strain, the corresponding Raman intensity exhibits a distinct polarization dependence. We compare a 2.5° twisted MoS2 bilayer, in which the maximal intrinsic moiré strain is anticipated, and a natural MoS2 bilayer with an intentionally introduced uniaxial strain. By analyzing the frequency shift of the E2g doublet and their polarization dependence, we can not only determine the direction of unintentional uniaxial strain in the twisted bilayer but also quantify both strain components. This simple strain characterization method based on far-field Raman spectra will facilitate the studies of electronic properties of moiré superlattices under the influence of combined intrinsic and external strains.In twisted van der Waals (vdW) bilayers, intrinsic strain associated with the moiré superlattice and unintentionally introduced uniaxial strain may be present simultaneously. Both strains are able to lift the degeneracy of the E2g phonon modes in Raman spectra. Because of the different rotation symmetry of the two types of strain, the corresponding Raman intensity exhibits a distinct polarization dependence. We compare a 2.5° twisted MoS2 bilayer, in which the maximal intrinsic moiré strain is anticipated, and a natural MoS2 bilayer with an intentionally introduced uniaxial strain. By analyzing the frequency shift of the E2g doublet and their polarization dependence, we can not only determine the direction of unintentional uniaxial strain in the twisted bilayer but also quantify both strain components. This simple strain characterization method based on far-field Raman spectra will facilitate the studies of electronic properties of moiré superlattices under the influence of combined intrinsic and external strains.

Kim, D. S. ; Dominguez, R. C. ; Mayorga-Luna, R. ; Ye, D. ; Embley, J. ; Tan, T. ; Ni, Y. ; Liu, Z. ; Ford, M. ; Gao, F. Y. ; et al. Electrostatic moiré potential from twisted hexagonal boron nitride layers. Nature Materials 1–6.

Kim, D. S. ; Huang, D. ; Guo, C. ; Li, K. ; Rocca, D. ; Gao, F. Y. ; Choe, J. ; Lujan, D. ; Wu, T. - H. ; Lin, K. - H. ; et al. Anisotropic Excitons Reveal Local Spin Chain Directions in a van der Waals Antiferromagnet. Advanced Materials 2206585.

Choi, J. ; Embley, J. ; Blach, D. D. ; Perea-Causín, R. ; Erkensten, D. ; Kim, D. S. ; Yuan, L. ; Yoon, W. Y. ; Taniguchi, T. ; Watanabe, K. ; et al. Fermi Pressure and Coulomb Repulsion Driven Rapid Hot Plasma Expansion in a van der Waals Heterostructure. Nano Letters.

Manzanares-Negro, Y. ; Quan, J. ; Rassekh, M. ; Moaied, M. ; Li, X. ; Ares, P. ; Palacios, J. J. ; Gomez-Herrero, J. ; Gomez-Navarro, C. Low resistance electrical contacts to few-layered MoS2 by local pressurization. 2D Materials 10, 021003.

Huang, D. ; Sampson, K. ; Ni, Y. ; Liu, Z. ; Liang, D. ; Watanabe, K. ; Taniguchi, T. ; Li, H. ; Martin, E. ; Levinsen, J. ; et al. Quantum Dynamics of Attractive and Repulsive Polarons in a Doped MoSe 2 Monolayer. Physical Review X 13, 011029.