Spatially Separated Superconductivity and Enhanced Charge-Density-Wave Ordering in an IrTe2 Nanoflake

Yanpeng Song; Fanqi Meng; Tianping Ying; Jun Deng; Junjie Wang; Xu Han; Qinghua Zhang; Yuan Huang; Jian-Gang Guo; Xiaolong Chen

doi:10.1021/acs.jpclett.1c03302

Spatially Separated Superconductivity and Enhanced Charge-Density-Wave Ordering in an IrTe₂ Nanoflake

J Phys Chem Lett. 2021 Dec 30;12(51):12180-12186. doi: 10.1021/acs.jpclett.1c03302. Epub 2021 Dec 17.

Authors

Yanpeng Song¹, Fanqi Meng¹, Tianping Ying¹, Jun Deng^{1

2}, Junjie Wang^{1

2}, Xu Han^{1

3}, Qinghua Zhang¹, Yuan Huang³, Jian-Gang Guo^{1

4}, Xiaolong Chen^{1

4

2}

Affiliations

¹ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
² University of Chinese Academy of Sciences, Beijing 100049, China.
³ Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China.
⁴ Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China.

PMID: 34918519
DOI: 10.1021/acs.jpclett.1c03302

Abstract

The interplay among collective electronic states like superconductivity (SC) and charge density wave (CDW) is of significance in transition metal dichalcogenides. To date, a consensus on the relationship between SC and CDW has not been established in IrTe₂. Here we use the Au-assisted exfoliation method to cleave IrTe₂ down to 10 nm. A striking feature is the concurrence of phase separation in a single piece of nanoflake, i.e., the superconducting (P3̅m1) and CDW (P3̅) phases. In the former area, the dimensional fluctuations suppress the CDW ordering and induce SC at 3.5 K. The CDW area at the phase boundary shows enhanced T_CDW at 605 K (T_CDW = 280 K in the bulk phase), which is accompanied by a unique wrinkle. Detailed analyses suggest that the strain-induced bond breaking of Te-Te dimers favors the CDW. Our works provide compelling evidence of competition between SC and CDW in IrTe₂.