6 papers
Wannier representation of Floquet topological states
Masaya Nakagawa, Robert-Jan Slager, Sho Higashikawa +1
A universal feature of topological insulators is that they cannot be adiabatically connected to an atomic limit, where individual lattice sites are completely decoupled. This prope…
Floquet engineering of classical systems
Sho Higashikawa, Hiroyuki Fujita, Masahiro Sato
We develop the Floquet-Magnus expansion for a classical equation of motion under a periodic drive that is applicable to both isolated and open systems. For classical systems, known…
Collective modes of vortex lattices in two-component Bose-Einstein condensates under synthetic gauge fields
Takumi Yoshino, Shunsuke Furukawa, Sho Higashikawa +1
We study collective modes of vortex lattices in two-component Bose-Einstein condensates subject to synthetic magnetic fields in mutually parallel or antiparallel directions. By mea…
Floquet chiral magnetic effect
Sho Higashikawa, Masaya Nakagawa, Masahito Ueda
A single Weyl fermion, which is prohibited in static lattice systems by the Nielsen-Ninomiya theorem, is shown to be realized in a periodically driven three-dimensional lattice sys…
Topological unification of time-reversal and particle-hole symmetries in non-Hermitian physics
Kohei Kawabata, Sho Higashikawa, Zongping Gong +2
Topological phases are enriched in non-equilibrium open systems effectively described by non-Hermitian Hamiltonians. While several properties unique to non-Hermitian topological sy…
Topological phases of non-Hermitian systems
Zongping Gong, Yuto Ashida, Kohei Kawabata +3
Recent experimental advances in controlling dissipation have brought about unprecedented flexibility in engineering non-Hermitian Hamiltonians in open classical and quantum systems…