130 citations · 710 across the 21 of their papers we have counts for
8 papers · 1 filter
Cyclotron radiation and emission in graphene
Takahiro Morimoto, Yasuhiro Hatsugai, Hideo Aoki
Peculiarity in the cyclotron radiation and emission in graphene is theoretically examined in terms of the optical conductivity and relaxation rates to propose that graphene in magn…
Topological Classification of Gapped Spin Chains :Quantized Berry Phase as a Local Order Parameter
Takaaki Hirano, Hosho Katsura, Yasuhiro Hatsugai
We characterize several phases of gapped spin systems by local order parameters defined by quantized Berry phases. This characterization is topologically stable against any small p…
Nontrivial quantized Berry phases for itinerant spin liquids
Isao Maruyama, Yasuhiro Hatsugai
Quantized Berry phases as local order parameters in t-J models are studied. A texture pattern of the local order parameters is topologically stable due to the quantization of non-A…
Levitation and percolation in quantum Hall systems with correlated disorder
Hui Song, Isao Maruyama, Yasuhiro Hatsugai
We investigate the integer quantum Hall system in a two dimensional lattice model with spatially correlated disorder by using the efficient method to calculate the Chern number pro…
Charge and spin stripe in LaSrNiO (x=1/3,1/2)
S. Yamamoto, T. Fujiwara, Y. Hatsugai
Electronic structure of stripe ordered LaSrNiO is investigated. The system with x=1/3 is insulator, in LSDA+U calculations, and shows charge and spin stripe, co…
Entanglement Entropy of One-dimensional Gapped Spin Chains
Takaaki Hirano, Yasuhiro Hatsugai
We investigate the entanglement entropy (EE) of gapped S=1 and spin chains with dimerization. We find that the effective boundary degrees of freedom as edge states contribu…