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arXiv · 0712.3189

Energy spectrum of bound-spinons in the quantum Ising spin-chain ferromagnet

S. B. Rutkevich
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Abstract

We study the excitation energy spectrum in the S=1/2 ferromagnetic Ising spin chain with the easy axis z in a magnetic field h={h_x,0,h_z}. According to Wu and McCoy's scenario of weak confinement, the fermionic spinon excitations (kinks), being free at h_z = 0 in the ordered phase, are coupled into bosonic bound states at arbitrary small h_z. We calculate the energy spectrum of such excitations in the leading order in small h_z, using different perturbative methods developed for the similar problem in the Ising field theory.

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S. B. Rutkevich. 2007-12-19. Energy spectrum of bound-spinons in the quantum Ising spin-chain ferromagnet. https://doi.org/10.1007/s10955-008-9495-1

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