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arXiv · 2107.08656

Counterdiabatic route for preparation of state with long-range topological order

Sanjeev Kumar·Shekhar Sharma·Vikram Tripathi
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Abstract

We propose here a counterdiabatic (CD) strategy for fast preparation of a state with long-range topological order by magnetic field tuning of an initial separable state. For concreteness, we consider the ground state of the honeycomb Kitaev model whose long-range topological order together with the anyonic excitations make it an interesting candidate for fault-tolerant universal quantum computation and storage. The required CD perturbation is found to be local, having the form of the off-diagonal exchange interactions reminiscent of trigonal deformations in Kitaev Hamiltonians. We show that the counterdiabatically produced state can have high fidelity and retain numerous desired entanglement properties.

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Sanjeev Kumar, Shekhar Sharma, Vikram Tripathi. 2021-07-19. Counterdiabatic route for preparation of state with long-range topological order. https://doi.org/10.1103/physrevb.104.245113

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