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arXiv · 1309.2013

Generation of chiral solitons in antiferromagnetic chains by a quantum quench

Barbara Bravo·Ariel Dobry·Diego Mastrogiuseppe·Claudio Gazza
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Abstract

We analyze the time evolution of a magnetic excitation in a spin-1/2 antiferromagnetic Heisenberg chain after a quantum quench. By a proper modulation of the magnetic exchange coupling, we prepare a static soliton of total spin 1/2 as an initial spin state. Using bosonization and a numerical time dependent density matrix renormalization group algorithm, we show that the initial excitation evolves to a state composed of two counter-propagating chiral states, which interfere to yield = 1/4 for each mode. We find that these dynamically generated states remain considerably stable as time evolution is carried out. We propose spin-Peierls materials and ultracold-atom systems as suitable experimental scenarios in which to conduct and observe this mechanism.

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Barbara Bravo, Ariel Dobry, Diego Mastrogiuseppe, Claudio Gazza. 2013-09-08. Generation of chiral solitons in antiferromagnetic chains by a quantum quench. https://doi.org/10.1103/physrevb.88.195125

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