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arXiv · 0809.2185

Quantum spin pump on a finite antiferromagnetic chain through bulk states

Nan-Hong Kuo·Sujit Sarkar·C. D. Hu
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Abstract

We studied the possibility of the spin pump in a S=1/2 antiferromagnetic chain. The spin chain is mapped into a fermion system and bosonization is utilized to transform the equation of motion to a sine-Gordon equation. The sine-Gordon equation on a finite chain with different boundary conditions is solved. Among numerous solutions, the static soliton is compatible with the original physical system. By varying adiabatically a angle in the phase space composed of applied electric and magnetic fields, the spin states change between the Neel state and dimer state and a quantized spin is transported by the bulk state from one end of the system to the other.

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Nan-Hong Kuo, Sujit Sarkar, C. D. Hu. 2008-11-18. Quantum spin pump on a finite antiferromagnetic chain through bulk states. https://arxiv.org/abs/0809.2185

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