skip to main content

DOE PAGESDOE PAGES

Title: Distinctive orbital anisotropy observed in the nematic state of a FeSe thin film

Nematic state, where the system is translationally invariant but breaks the rotational symmetry, has drawn great attentions recently due to experimental observations of such a state in both cuprates and iron-based superconductors. The mechanism of nematicity that is likely tied to the pairing mechanism of high-Tc, however, still remains controversial. Here, we studied the electronic structure of multilayer FeSe film by angle-resolved photoemission spectroscopy (ARPES). We found that the FeSe film enters the nematic state around 125 K, while the electronic signature of long range magnetic order has not been observed down to 20K indicating the non-magnetic origin of the nematicity. The band reconstruction in the nematic state is characterized by the splitting of the dxz and dyz bands. More intriguingly, such energy splitting is strong momentum dependent with the largest band splitting of ~80 meV at the zone corner. The simple on-site ferro-orbital ordering is insufficient to reproduce the nontrivial momentum dependence of the band reconstruction. Instead, our results suggest that the nearest-neighbor hopping of dxz and dyz is highly anisotropic in the nematic state, the origin of which holds the key in understanding the nematicity in iron-based superconductors.
Authors:
 [1] ;  [2] ;  [2] ;  [3] ;  [2] ;  [3] ;  [4] ;  [5] ;  [5] ;  [6] ;  [6] ;  [2] ;  [2] ;  [4]
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Materials and Energy Sciences; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Materials and Energy Sciences; Stanford Univ., CA (United States). Dept. of Physics and Dept. of Applied Physics
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Materials and Energy Sciences
  4. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource
  5. National Inst. of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Japan Science and Technology Agency (JST), Tokyo (Japan)
  6. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source
Publication Date:
Grant/Contract Number:
AC02-05CH11231; AC02-76SF00515
Type:
Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 94; Journal Issue: 11; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
OSTI Identifier:
1377500
Alternate Identifier(s):
OSTI ID: 1326699; OSTI ID: 1393078