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تسجيل مستخدم جديدMagnon bound states vs. anyonic Majorana excitations in the Kitaev honeycomb magnet $alpha$-RuCl$_3$
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The pure Kitaev honeycomb model harbors a quantum spin liquid in zero magnetic fields, while applying finite magnetic fields induces a topological spin liquid with non-Abelian anyonic excitations. This latter phase has been much sought after in Kitaev candidate materials, such as $alpha$-RuCl$_3$. Currently, two competing scenarios exist for the intermediate field phase of this compound ($B=7-10$ T), based on experimental as well as theoretical results: (i) conventional multiparticle magnetic excitations of integer quantum number vs. (ii) Majorana fermionic excitations of possibly non-Abelian nature with a fractional quantum number. To discriminate between these scenarios a detailed investigation of excitations over a wide field-temperature phase diagram is essential. Here we present Raman spectroscopic data revealing low-energy quasiparticles emerging out of a continuum of fractionalized excitations at intermediate fields, which are contrasted by conventional spin-wave excitations. The temperature evolution of these quasiparticles suggests the formation of bound states out of fractionalized excitations.
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Mott insulators with strong spin-orbit coupling have been proposed to host unconventional magnetic states, including the Kitaev quantum spin liquid. The 4$d$ system $alpha$-RuCl$_3$ has recently come into view as a candidate Kitaev system, with evide
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We report on the unusual behavior of the in-plane thermal conductivity ($kappa$) and torque ($tau$) response in the Kitaev-Heisenberg material $alpha$-RuCl$_3$. $kappa$ shows a striking enhancement with linear growth beyond H = 7 T, where magnetic or
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