Structural collapse and superconductivity in rare earth-doped CaFe2As2

Details Structural collapse and superconductivity in rare earth-doped CaFe2As2 Structural collapse and superconductivity in rare earth-doped CaFe2As2

2011-05-24

arxiv.org/abs/1105.4798v3

Phys. Rev. B 85, 024525 (2012)

Physics

Condensed Matter

Superconductivity

15 pages, 18 figures

Scientific paper

10.1016/j.physc.2012.01.020

Aliovalent rare earth substitution into the alkaline earth site of CaFe2As2 single-crystals is used to fine-tune structural, magnetic and electronic properties of this iron-based superconducting system. Neutron and single crystal x-ray scattering experiments indicate that an isostructural collapse of the tetragonal unit cell can be controllably induced at ambient pressures by choice of substituent ion size. This instability is driven by the interlayer As-As anion separation, resulting in an unprecedented thermal expansion coefficient of $180\times 10^{-6}$ K$^{-1}$. Electrical transport and magnetic susceptibility measurements reveal abrupt changes in the physical properties through the collapse as a function of temperature, including a reconstruction of the electronic structure. Superconductivity with onset transition temperatures as high as 47 K is stabilized by the suppression of antiferromagnetic order via chemical pressure, electron doping or a combination of both. Extensive investigations are performed to understand the observations of partial volume-fraction diamagnetic screening, ruling out extrinsic sources such as strain mechanisms, surface states or foreign phases as the cause of this superconducting phase that appears to be stable in both collapsed and uncollapsed structures.

Affiliated with

Also associated with

No associations

Rating

Structural collapse and superconductivity in rare earth-doped CaFe2As2 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Structural collapse and superconductivity in rare earth-doped CaFe2As2, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Structural collapse and superconductivity in rare earth-doped CaFe2As2 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-516177