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Signatures of the exciton gas phase and its condensation in monolayer 1T-ZrTe2

Journal Article · · Nature Communications
 [1];  [2];  [3];  [4];  [1];  [4];  [5];  [1];  [6];  [4];  [7];  [8];  [8];  [4];  [8];  [9];  [8];  [1]
  1. Chinese Academy of Sciences (CAS), Shanghai (China)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Univ. of Florida, Gainesville, FL (United States)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States); Shanghai Jiao Tong Univ. (China)
  4. ShanghaiTech University (China)
  5. Stanford Univ., CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Kangwon National Univ., Chuncheon (Korea, Republic of)
  6. Pusan National Univ., Busan (Korea, Republic of)
  7. Chinese Academy of Sciences (CAS), Shanghai (China); Univ. of Science and Technology of China, Hefei (China)
  8. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)
  9. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
+ Show Author Affiliations
The excitonic insulator (EI) is a Bose-Einstein condensation (BEC) of excitons bound by electron-hole interaction in a solid, which could support high-temperature BEC transition. The material realization of EI has been challenged by the difficulty of distinguishing it from a conventional charge density wave (CDW) state. In the BEC limit, the preformed exciton gas phase is a hallmark to distinguish EI from conventional CDW, yet direct experimental evidence has been lacking. Here we report a distinct correlated phase beyond the 2×2 CDW ground state emerging in monolayer 1T-ZrTe2 and its investigation by angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy (STM). The results show novel band- and energy-dependent folding behavior in a two-step process, which is the signatures of an exciton gas phase prior to its condensation into the final CDW state. Our findings provide a versatile two-dimensional platform that allows tuning of the excitonic effect.
Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
Chinese Academy of Sciences (CAS); National Key R&D Program of China; National Natural Science Foundation of China (NSFC); National Research Foundation of Korea (NRF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
Grant/Contract Number:
AC02-05CH11231; AC02-76SF00515
OSTI ID:
1969973
Journal Information:
Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 14; ISSN 2041-1723
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English

References (40)

Exciton condensation in an intermediate valence compound: TmSe0.45Te0.55 journal June 2001
An updated version of wannier90: A tool for obtaining maximally-localised Wannier functions journal August 2014
Evolution of the Electronic Properties of ZrX2 (X = S, Se, or Te) Thin Films under Varying Thickness journal January 2021
Semiconductor–Metal Phase Transition and Emergent Charge Density Waves in 1T-ZrX2 (X = Se, Te) at the Two-Dimensional Limit journal January 2022
Possible Excitonic Insulating Phase in Quantum-Confined Sb Nanoflakes journal July 2019
Massless Dirac Fermions in ZrTe 2 Semimetal Grown on InAs(111) by van der Waals Epitaxy journal January 2018
Transition from Semimetal to Semiconductor in ZrTe 2 Induced by Se Substitution journal December 2019
Bose–Einstein condensation of excitons in bilayer electron systems journal December 2004
Collapse of long-range charge order tracked by time-resolved photoemission at high momenta journal March 2011
Probing excitonic dark states in single-layer tungsten disulphide journal August 2014
Zero-gap semiconductor to excitonic insulator transition in Ta2NiSe5 journal February 2017
Emergence of coherence in the charge-density wave state of 2H-NbSe2 journal February 2015
Giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor journal August 2014
Evidence for a topological excitonic insulator in InAs/GaSb bilayers journal December 2017
Multiple mobile excitons manifested as sidebands in quasi-one-dimensional metallic TaSe3 journal February 2022
Electrical control of charged carriers and excitons in atomically thin materials journal January 2018
Detecting photoelectrons from spontaneously formed excitons journal July 2021
Evidence for a monolayer excitonic insulator journal December 2021
Evidence for equilibrium exciton condensation in monolayer WTe2 journal December 2021
Strongly correlated excitonic insulator in atomic double layers journal October 2021
Q uantum ESPRESSO toward the exascale journal April 2020
Coexistence of the charge density wave state and linearly dispersed energy band in 1T-ZrTe2 monolayer journal February 2022
Excitonic condensation in systems of strongly correlated electrons journal July 2015
Excitonic Insulator journal June 1967
Metal-chalcogen bond-length induced electronic phase transition from semiconductor to topological semimetal in ZrX2 ( X=Se and Te) journal April 2020
Slave-boson field fluctuation approach to the extended Falicov-Kimball model: Charge, orbital, and excitonic susceptibilities journal June 2011
Molecular-beam epitaxy and robust superconductivity of stoichiometric FeSe crystalline films on bilayer graphene journal July 2011
Photoemission signature of excitons journal June 2018
Exciton Condensation Driving the Periodic Lattice Distortion of 1 T − TiSe 2 journal March 2011
Fractional Excitonic Insulator journal September 2018
Reproduction of the Charge Density Wave Phase Diagram in 1 T − TiSe 2 Exposes its Excitonic Character journal November 2018
Disorder Quenching of the Charge Density Wave in ZrTe 3 journal January 2019
Spin-Triplet Excitonic Insulator: The Case of Semihydrogenated Graphene journal April 2020
Excitonic Phases journal August 1967
Excitonic insulator phase in TmSe 0.45 Te 0.55 journal November 1991
Evidence for an Excitonic Insulator Phase in 1 T − TiSe 2 journal October 2007
Widely tunable band gap in a multivalley semiconductor SnSe by potassium doping journal May 2018
Coherent order parameter oscillations in the ground state of the excitonic insulator Ta 2 NiSe 5 journal March 2018
Direct Observation of Nodes and Twofold Symmetry in FeSe Superconductor journal June 2011
Signatures of exciton condensation in a transition metal dichalcogenide journal December 2017

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Related Subjects

36 MATERIALS SCIENCE
Electronic properties and materials
Surfaces
interfaces and thin films
Two-dimensional materials