14 papers
Strong disorder effects of a Dirac fermion with a random vector field
T. Fukui
We study a Dirac fermion model with a random vector field, especially paying attention to a strong disorder regime. Applying the bosonization techniques, we first derive an equival…
Spectral flow of non-hermitian Heisenberg spin chain with complex twist
T. Fukui, N. Kawakami
We investigate the spectral flow of the integrable non-hermitian Heisenberg spin chain under boundary conditions with complex twist angle. It is shown that the period of the spectr…
Mixed-Spin Ladders and Plaquette Spin Chains
A. Koga, S. Kumada, N. Kawakami +1
We investigate low-energy properties of a generalized spin ladder model with both of the spin alternation and the bond alternation, which allows us to systematically study not only…
Alternating-Spin Ladders
T. Fukui, N. Kawakami
We investigate a two-leg spin ladder system composed of alternating-spin chains with two-different kind of spins. The fixed point properties are discussed by using spin-wave analys…
Alternating spin chains with singlet ground states
T. Fukui, N. Kawakami
We investigate low-energy properties of the alternating spin chain model composed of spin and with a singlet ground state. After examining the spin-wave spectrum in det…
Spin Chains with Periodic Array of Impurities
T. Fukui, N. Kawakami
We investigate the spin chain model composed of periodic array of two kinds of spins and , which allows us to study the spin chains with impurities as well as the altern…