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Title: Angle-resolved photoemission spectroscopy with an in situ tunable magnetic field
Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for probing the momentum-resolved single-particle spectral function of materials. Historically, in situ magnetic fields have been carefully avoided as they are detrimental to the control of photoelectron trajectory during the photoelectron detection process. However, magnetic field is an important experimental knob for both probing and tuning symmetry-breaking phases and electronic topology in quantum materials. In this paper, we introduce an easily implementable method for realizing an in situ tunable magnetic field at the sample position in an ARPES experiment and analyze magnetic-field-induced artifacts in the ARPES data. Specifically, we identified and quantified three distinct extrinsic effects of a magnetic field: constant energy contour rotation, emission angle contraction, and momentum broadening. We examined these effects in three prototypical quantum materials, i.e., a topological insulator (Bi2Se3), an iron-based superconductor (LiFeAs), and a cuprate superconductor (Pb-Bi2Sr2CuO6+x), and demonstrate the feasibility of ARPES measurements in the presence of a controllable magnetic field. Our studies lay the foundation for the future development of the technique and interpretation of ARPES measurements of field-tunable quantum phases.  more » « less
Award ID(s):
2239171 2019004
PAR ID:
10474577
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
AIP publishing
Date Published:
Journal Name:
Review of Scientific Instruments
Volume:
94
Issue:
9
ISSN:
0034-6748
Page Range / eLocation ID:
093902
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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