Campus Units

Physics and Astronomy, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

6-1-2012

Journal or Book Title

Physical Review B

Volume

85

Issue

21

First Page

214515

DOI

10.1103/PhysRevB.85.214515

Abstract

We use point-contact spectroscopy (PCS) to probe AEFe2As2 (AE=Ca,Sr,Ba) and Fe1+yTe. For AE=Sr,Ba we detect orbital fluctuations above TS while for AE=Ca these fluctuations start below TS. Co doping preserves the orbital fluctuations while K doping suppresses it. The fluctuations are only seen at those dopings and temperatures where an in-plane resistive anisotropy is known to exist. We predict an in-plane resistive anisotropy of Fe1+yTe above TS. Our data are examined in light of the recent work by Lee and Phillips (arXiv:1110.5917v2). We also study how joule heating in the PCS junctions impacts the spectra. Spectroscopic information is only obtained from those PCS junctions that are free of heating effects while those PCS junctions that are in the thermal regime display bulk resistivity phenomena.

Comments

This article is published as Arham, H. Z., C. R. Hunt, W. K. Park, J. Gillett, S. D. Das, S. E. Sebastian, Z. J. Xu et al. "Detection of orbital fluctuations above the structural transition temperature in the iron pnictides and chalcogenides." Physical Review B 85, no. 21 (2012): 214515. DOI: 10.1103/PhysRevB.85.214515. Posted with permission.

Copyright Owner

American Physical Society

Language

en

File Format

application/pdf

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