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Title: Low work function in the 122-family of iron-based superconductors

Journal Article · · Physical Review Materials
ORCiD logo [1];  [2];  [3];  [3];  [4];  [3];  [3];  [5];  [5];  [6];  [4]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Tel Aviv Univ., Ramat Aviv (Israel)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States). Geballe Lab. for Advanced Materials
  4. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)
  5. Nanjing Univ. (China)
  6. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States). Geballe Lab. for Advanced Materials and Dept. of Physics

Herein we determine the work functions of the iron arsenic compounds A Fe 2 As 2 ( A = Ca , Ba , Cs ) using photoemission spectroscopy to be 2.7 eV for CaFe 2 As 2 , 1.8 eV for BaFe 2 As 2 , and 1.3 eV for CsFe 2 As 2 . The work functions of these 122 iron-based superconductors track those of the elementary metal A but are substantially smaller. The most likely explanation of this observation is that the cleaving surface exposes only half an A -layer. The low work function and good photoemission cross section of BaFe 2 As 2 and CsFe 2 As 2 enable photoemission even from a common white LED light.

Research Organization:
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
Sponsoring Organization:
Alexander von Humboldt Foundation; German Science Foundation (DFG); Gabilan Stanford Graduate Fellowship; National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
Grant/Contract Number:
AC02-76SF00515; DGE-114747; AC02-05CH11231
OSTI ID:
1605595
Alternate ID(s):
OSTI ID: 1603199
Journal Information:
Physical Review Materials, Vol. 4, Issue 3; ISSN 2475-9953
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 5 works
Citation information provided by
Web of Science

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Figures / Tables (6)