Exploring Spatial Variations in the Charge Density Wave State in 1T-TiSe₂ Using STM and DFT
ORAL
Abstract
The transition metal dichalcogenide 1T-TiSe₂ is a quasi-two-dimensional layered material that exhibits a bulk charge density wave (CDW) transition near 200 K. The compound’s crystal structure consists of layers containing TiSe₆ octahedra with neighboring layers stacked along the c-axis, coupled by van der Waals interactions. Below the bulk CDW transition, 1T-TiSe₂ exhibits a commensurate 2a₀ × 2a₀ × 2c₀ superstructure.
In this work, we present temperature-dependent scanning tunneling microscopy (STM) measurements of 1T-TiSe₂ to investigate the evolution of the CDW state across the bulk transition. Our studies reveal spatial variations in the CDW state below the transition temperature and we examine their correlation with local lattice strain and defects. Combining Density Functional Theory (DFT) calculations with our STM measurements, we study the interplay between electronic structure, lattice distortions, strain and the established the CDW phase.
*This work is supported by NSF Grant No. DMR-1904918.
In this work, we present temperature-dependent scanning tunneling microscopy (STM) measurements of 1T-TiSe₂ to investigate the evolution of the CDW state across the bulk transition. Our studies reveal spatial variations in the CDW state below the transition temperature and we examine their correlation with local lattice strain and defects. Combining Density Functional Theory (DFT) calculations with our STM measurements, we study the interplay between electronic structure, lattice distortions, strain and the established the CDW phase.
*This work is supported by NSF Grant No. DMR-1904918.
**This work is supported by NSF Grant No. DMR-1904918.
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Presenters
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Susree Mohapatra
- Clark University