Magnetic-field-induced charge order in the filled skutterudite SmRuP; Evidence from resonant and nonresonant X-ray diffraction

Matsumura, Takeshi*; Michimura, Shinji*; Inami, Toshiya; Hayashi, Yuya*; Fushiya, Kengo*; Matsuda, Tatsuma*; Higashinaka, Ryuji*; Aoki, Yuji*; Sugawara, Hitoshi*

The antiferromagnetic ordered phase below = 16.5 K and the unresolved intermediate phase between and (= 14 K) in SmRuP have been studied by resonant and nonresonant X-ray diffraction. In the intermediate phase, nonresonant Thomson scattering with = (1,0,0) is induced by applying a magnetic field. This phenomena is caused by atomic displacements reflecting the charge order in the band, as predicted theoretically. Simultaneously, the antiferromagnetic moment of Sm is enhanced along the field direction, which is considered to reflect the staggered ordering of the - crystal-field states. The present results show that the orbital-dependent - hybridization in association with the nesting instability in the band gives rise to the unconventional charge order similarly with PrRuP and PrFeP.