第6回　物理工学科教室談話会（講師：Dr. Maria Hermanns）

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要旨：
One of the most intriguing phenomena in strongly correlated systems is the fractionalization of quantum numbers ― familiar examples include the spin-charge separation in one-dimensional metallic systems, the fractionalization of the electron in fractional quantum Hall states or the emergence of monopoles in spin ice.
In this talk, I will discuss the fractionalization of magnetic moments in a certain class of Mott insulators, in which the emergent degrees of freedom are Majorana fermions that form an (almost) conventional metal. The origin of such a dichotomous state is elucidated by a family of exactly solvable models of frustrated quantum magnets in three dimensions, which might be realized in a class of recently synthesized Iridate compounds. These models thereby provide the first analytical tractable examples of long sought-after quantum spin liquids with a spinon Fermi surface and even an entire new class of quantum spin liquids ― a so-called Weyl spin liquid, in which the fractionalized degrees of freedom form a topological semi-metal.
紹介教員：今田正俊教授、求幸年准教授