3 papers
cond-mat.mes-hall2001
Method of Collective Degrees of Freedom in Spin Coherent State Path Integral
Junya Shibata, Shin Takagi
We present a detailed field theoretic description of those collective degrees of freedom (CDF) which are relevant to study macroscopic quantum dynamics of a quasi-one-dimensional f…
cond-mat.mes-hall1999
Macroscopic Quantum Dynamics of a Free Domain Wall in a Ferromagnet
Junya Shibata, Shin Takagi
We study macroscopic quantum dynamics of a free domain wall in a quasi-one-dimensional ferromagnet by use of the spin-coherent-state path integral in {\it discrete-time} formalism.…
quant-ph1998
A Note on (Spin-) Coherent-State Path Integral
Junya Shibata, Shin Takagi
It is pointed out that there are some fundamental difficulties with the frequently used continuous-time formalism of the spin-coherent-state path integral. They arise already in a…