Phonon-induced quadrupolar ordering of the magnetic superconductor TmNi$_2$B$_2$C

N. H. Andersen; J. Jensen; T. B. S. Jensen; M. v. Zimmermann; R. Pinholt; A. B. Abrahamsen; K. Noegaard Toft; P. Hedegard; P. C. Canfield

doi:10.1103/physrevb.73.020504

arXiv · cond-mat/0508630

Phonon-induced quadrupolar ordering of the magnetic superconductor TmNi$_2$B$_2$C

N. H. Andersen·J. Jensen·T. B. S. Jensen·M. v. Zimmermann·R. Pinholt·A. B. Abrahamsen·K. Noegaard Toft·P. Hedegard·P. C. Canfield

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Abstract

We present synchrotron x-ray diffraction studies revealing that the lattice of thulium borocarbide is distorted below T_Q = 13.5 K at zero field. T_Q increases and the amplitude of the displacements is drastically enhanced, by a factor of 10 at 60 kOe, when a magnetic field is applied along [100]. The distortion occurs at the same wave vector as the antiferromagnetic ordering induced by the a-axis field. A model is presented that accounts for the properties of the quadrupolar phase and explains the peculiar behavior of the antiferromagnetic ordering previously observed in this compound.

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N. H. Andersen, J. Jensen, T. B. S. Jensen, M. v. Zimmermann, R. Pinholt, A. B. Abrahamsen, K. Noegaard Toft, P. Hedegard, P. C. Canfield. 2005-08-26. Phonon-induced quadrupolar ordering of the magnetic superconductor TmNi$_2$B$_2$C. https://doi.org/10.1103/physrevb.73.020504

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