Dependence of the absolute value of the penetration depth in (Ba1–xKx)Fe2As2 on doping

Almoalem, Avior; Yagil, Alon; Cho, Kyuil; Teknowijoyo, Serafim; Tanatar, Makariy A.; Prozorov, Ruslan; Liu, Yong; Lograsso, Thomas A.; Auslaender, Ophir M.

doi:10.1103/PhysRevB.98.054516

Dependence of the absolute value of the penetration depth in $({Ba}_{1 - x} K_{x}) {Fe}_{2} {As}_{2}$ on doping

Journal Article · Mon Aug 27 00:00:00 EDT 2018 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.98.054516· OSTI ID:1471219

Almoalem, Avior ^[1]; Yagil, Alon ^[1]; Cho, Kyuil ^[2]; Teknowijoyo, Serafim ^[2]; Tanatar, Makariy A. ^[2]; Prozorov, Ruslan ^[2]; Liu, Yong ^[3]; Lograsso, Thomas A. ^[2]; Auslaender, Ophir M. ^[1]

Technion–Israel Institute of Technology, Haifa (Israel)
Ames Lab. and Iowa State Univ., Ames, IA (United States)
Ames Lab., Ames, IA (United States)

Here, we report magnetic force microscopy (MFM) measurements on the iron-based superconductor Ba_1–xK_xFe₂As₂. By measuring locally the Meissner repulsion with the magnetic MFM tip, we determine the absolute value of the in-plane magnetic penetration depth (λ_ab) in underdoped, optimally doped, and overdoped samples. The results suggest an abrupt increase of λ_ab as doping is increased from x_opt, which is potentially related to the presence of a quantum critical point. The response of superconducting vortices to magnetic forces exerted by the MFM tip for x = 0.19 and 0.58 is compatible with previously observed structural symmetries at those doping levels.

View Accepted Manuscript (DOE)

Research Organization:: Ames Laboratory (AMES), Ames, IA (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

Grant/Contract Number:: AC02-07CH11358

OSTI ID:: 1471219

Alternate ID(s):: OSTI ID: 1466861

Report Number(s):: IS-J--9720

Journal Information:: Physical Review B, Journal Name: Physical Review B Journal Issue: 5 Vol. 98; ISSN 2469-9950; ISSN PRBMDO

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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