Magnetoentropic Mapping of GaV4S8 and GaV4Se8

The development of next-generation spintronic devices relies in a large part on engineering subtle magnetic phase transitions which control the formation of long-wavelength spin textures.

Stephen Wilson and Ram Seshadri (UCSB)

The  development  of  next-generation  spintronic  devices  relies  in  a large  part  on  engineering  subtle  magnetic  phase  transitions  which control  the  formation  of  long-wavelength  spin  textures.  Topologically non-trivial  spin  textures  such  as  skyrmion  lattices  are  of  interest  for high-density, energy-efficient non-volatile magnetic memory schemes. Here  we  demonstrate  the  utility  of  the  magnetoentropic  mapping method  in  combination  with  computational  models  to  rapidly  identify magnetic   textures   such   as   cycloids   and   skyrmions   in   uniaxial systems.  We  obtain  excellent  agreement  with  previously  reported magnetic    phase    diagrams    in    GaV4S8    and    GaV4Se8.   A    low temperature,   high   entropy   signature   is   identified   in   GaV4Se8concurrent    with    unidentified    phase    regions.    These    results demonstrate that magnetoentropic mapping informed by computational  models  of  entropic  susceptibility  can  provide  a  rapid, unambiguous  measurement  of  cycloid/skyrmion  phase  boundaries  in model     uniaxial     systems     and     thereby     facilitate     the     rapid characterization of similar skyrmion phase diagrams.

Designing Materials to Revolutionize and Engineer our Future (DMREF)