Magnetic phase transitions, metastable states, and magnetic hysteresis in the antiferromagnetic compounds Fe 0.5 TiS 2−y Se y

摘要: The phase transitions and magnetization processes in the antiferromagnetic compounds $\mathrm{Fe}{}_{0.5}\mathrm{TiS}{}_{2\ensuremath{-}y}\mathrm{Se}{}_{y}\phantom{\rule{4pt}{0ex}}[\mathrm{FeTi}{}_{2}$(S,$\mathrm{Se}){}_{4}]$ with an ordered layered crystal structure of $\mathrm{Cr}{}_{3}{\mathrm{S}}_{4}$ type have been studied by using x-ray diffraction, measurements specific heat, electrical resistivity, magnetoresistance, steady pulsed magnetic fields together calculations within Ising model accounting magnetoelastic interactions. change from spin-flip to spin-flop transition a monotonic growth critical field $\ensuremath{\sim}50$ kOe at $y=0$ up 470 $y=2$ has observed Se for S substitution (AFM) $\mathrm{Fe}{}_{0.5}\mathrm{TiS}{}_{2\ensuremath{-}y}\mathrm{Se}{}_{y}$. In selenium-poor $(yl0.5)$, field-induced AFM-FM low temperatures is accompanied ultrasharp changes magnetoresistance huge hysteresis. presence remnant these after application indicates formation metastable FM state. Despite AFM ground state, $\mathrm{Fe}{}_{0.5}\mathrm{TiS}{}_{2\ensuremath{-}y}\mathrm{Se}{}_{y}$ $yl0.5$ behave as high-anisotropic Ising-type ferromagnets coercive ${H}_{c}$ $\ensuremath{\sim}60$ kOe. It shown, that interactions may be responsible high-coercive state antiferromagnets.