Magnetoelastic phase diagram ofTbNi2B2C

Abstract

The magnetic phase diagram of the quaternary borocarbide TbNi 2 B 2 C is investigated by direct means and by studying magnetically induced modifications of the crystal structure. Detailed superconducting quantum interference device measurements reveal a complex phase diagram with five distinct magnetic phases. The phase boundaries are mapped out comprehensively. Synchrotron hard x-ray measurements in applied magnetic fields are employed to probe the magnetoelastic distortions throughout the phase diagram. The determination of the wave vectors of these field-induced lattice deformations suggests a range of commensurate spin-slip-type magnetic structures at low temperatures with wave vectors of the form (q,0,0) with q = 6/11 and 5/9. The proposed magnetic structures yield values of magnetization well in-line with observations. The scattering intensity due to the magnetoelastic deformations exhibits a drastic jump at the phase boundary at 1.3 T and low temperatures.

Nanowire reconstruction under external magnetic fields

“…Even if the energetic differences are tiny, external fields can change notably the electronic configuration, effectively preventing certain bonds or enhancing others, thus giving rise to subtle changes in the surface lattice parameters. Indeed, both bulk magnetoelastic lattice distortions [8,9] and spinphonon interactions [10,11] have attracted considerable interest. Moreover, examples of magnetization mediated surface reconstructions have been reported [12,13], and the complementary concept of magnetic reconstruction, where the surface spins present a different symmetry from the bulk, has also been discussed in the literature [14][15][16][17].…”