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arXiv · 2604.27053

Resolving spurious topological entanglement entropy in stabilizer codes

Peilun Han·Zijian Liang·Yifei Wang·Bowen Yang·Yingfei Gu·Yu-An Chen
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Abstract

Topological entanglement entropy (TEE) is a key diagnostic of long-range entanglement in two-dimensional gapped phases of matter, but it can suffer from spurious contributions that overestimate the total quantum dimension of the underlying topological order. In this work, we identify the microscopic origin of spurious TEE and introduce a concave partition for computing the Levin-Wen TEE of translation-invariant stabilizer codes of prime-dimensional qudits. We rigorously prove that this prescription is free of spurious contributions. As a complementary probe, we study bivariate bicycle codes on a bipartite cylinder and show that the entanglement entropy depends sensitively on the cylinder circumference, revealing topological frustration of the underlying anyons.

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Peilun Han, Zijian Liang, Yifei Wang, Bowen Yang, Yingfei Gu, Yu-An Chen. 2026-04-29. Resolving spurious topological entanglement entropy in stabilizer codes. https://arxiv.org/abs/2604.27053

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