Continuous Phase Transition without Gap Closing in Non-Hermitian Quantum Many-Body Systems

Norifumi Matsumoto, Kohei Kawabata, Yuto Ashida, Shunsuke Furukawa, Masahito Ueda

研究成果: Article査読

69 被引用数 (Scopus)

抄録

Contrary to the conventional wisdom in Hermitian systems, a continuous quantum phase transition between gapped phases is shown to occur without closing the energy gap Δ in non-Hermitian quantum many-body systems. Here, the relevant length scale ζ≃vLR/Δ diverges because of the breakdown of the Lieb-Robinson bound on the velocity (i.e., unboundedness of vLR) rather than vanishing of the energy gap Δ. The susceptibility to a change in the system parameter exhibits a singularity due to nonorthogonality of eigenstates. As an illustrative example, we present an exactly solvable model by generalizing Kitaev's toric-code model to a non-Hermitian regime.

本文言語English
論文番号260601
ジャーナルPhysical review letters
125
26
DOI
出版ステータスPublished - 2020 12月 21

ASJC Scopus subject areas

  • 物理学および天文学一般

フィンガープリント

「Continuous Phase Transition without Gap Closing in Non-Hermitian Quantum Many-Body Systems」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル