Uniaxial pressure effect on structural and magnetic phase transitions in NaFeAs and its comparison with as-grown and annealed BaFe2As2

Journal Article · Tue Jan 01 00:00:00 EST 2013 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.87.184511· OSTI ID:1092286

Song, Yu ^[1]; Carr, Scott Victor ^[1]; Lu, Xingye ^[2]; Zhang, Chenglin ^[1]; Luttrell, N. F. ^[3]; Zhao, Yang ^[4]; Lynn, J. W. ^[4]; Dai, Pengcheng ^[1]; Sims, Zachary ^[3]; Chi, Songxue ^[1]

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1. ORNL
2. University of Tennessee (UT)
3. University of Tennessee, Knoxville (UTK)
4. National Institute of Standards and Technology (NIST)

We use neutron scattering to study the effect of uniaxial pressure on the tetragonal-toorthorhombic structural (Ts) and paramagnetic-to-antiferromagnetic (TN) phase transitions in NaFeAs and compare the outcome with similar measurements on as-grown and annealed BaFe2As2. In previous work on as-grown BaFe2As2, uniaxial pressure necessary to detwin the sample was found to induce a significant increase in zero pressure TN and Ts. However, we find that similar uniaxial pressure used to detwin NaFeAs and annealed BaFe2As2 has a very small effect on their TN and Ts. Since transport measurements on these samples still reveal resistivity anisotropy above TN and Ts, we conclude that such anisotropy cannot be due to uniaxial strain induced TN and Ts shifts, but must arise from intrinsic electronic anisotropy in these materials.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1092286
• Journal Information: Physical Review B, Vol. 87, Issue 18; ISSN 1098--0121
• Country of Publication: United States
• Language: English