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arXiv · 2303.04806

Braiding fractional quantum Hall quasiholes on a superconducting quantum processor

Ammar Kirmani·Derek S. Wang·Pouyan Ghaemi·Armin Rahmani
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Abstract

Direct experimental detection of anyonic exchange statistics in fractional quantum Hall systems by braiding the excitations and measuring the wave-function phase is an enormous challenge. Here, we use a small, noisy quantum computer to emulate direct braiding within the framework of a simplified model applicable to a thin cylinder geometry and measure the topological phase. Our algorithm first prepares the ground state with two quasiholes. It then applies a unitary operation controlled by an ancilla, corresponding to a sequence of adiabatic evolutions that takes one quasihole around the other. We finally extract the phase of the wave function from measuring the ancilla with a compound error mitigation strategy. Our results open a new avenue for studying braiding statistics in fractional Hall states.

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Ammar Kirmani, Derek S. Wang, Pouyan Ghaemi, Armin Rahmani. 2023-03-08. Braiding fractional quantum Hall quasiholes on a superconducting quantum processor. https://doi.org/10.1103/physrevb.108.064303

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