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arXiv · 2305.08357

Field-driven spatiotemporal manipulation of Majorana zero modes in a Kitaev spin liquid

Chihiro Harada·Atsushi Ono·Joji Nasu
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Abstract

The Kitaev quantum spin liquid possesses two fractional quasiparticles, itinerant Majorana fermions and localized visons. It provides a promising platform for realizing a Majorana zero mode trapped by a vison excitation. This local mode behaves as a non-Abelian anyon capable of applications to quantum computation. However, creating, observing, and manipulating visons remain challenging even in the pristine Kitaev model. Here, we propose a theory to control visons enabled by a time-dependent local magnetic field in the Kitaev spin liquid. Examining the time evolution of the magnetic state, we demonstrate that a vison follows a locally applied field sweeping in the system. We clarify that one can move a vison accompanied by a Majorana zero mode by choosing the velocity and shape of the local field appropriately. In particular, the controllability of visons using local fields shows nonlinear behavior for its strength, which originates from interactions between Majorana fermions and visons. The present results suggest that itinerant Majorana fermions other than zero modes play a crucial role in vison transport. Our finding will offer a guideline for controlling Majorana zero modes in the Kitaev quantum spin liquid.

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Chihiro Harada, Atsushi Ono, Joji Nasu. 2023-05-15. Field-driven spatiotemporal manipulation of Majorana zero modes in a Kitaev spin liquid. https://doi.org/10.1103/physrevb.108.l241118

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