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arXiv · 2509.09663

Bogoliubov quasi-particles in superconductors are integer-charged particles inapplicable for braiding quantum information

Zhiyu Fan·Wei Ku
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Abstract

We present a rigorous proof that under a number-conserving Hamiltonian, one-body quasi-particles generally possess quantized charge and inertial mass identical to the bare particles. It follows that, Bogoliubov zero modes in the vortex (or on the edge) of superconductors $\textit{cannot}$ be their own anti-particles capable of braiding quantum information. As such, the heavily pursued Majorana zero mode-based route for quantum computation requires a serious re-consideration. This study further reveals the conceptual challenge in preparing and manipulating braid-able quantum states via physical thermalization or slow external fields. These profound results should reignite the long-standing quest for a number-conserving theory of superconductivity and superfluidity without fictitiously breaking global U(1) symmetry.

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Zhiyu Fan, Wei Ku. 2025-09-11. Bogoliubov quasi-particles in superconductors are integer-charged particles inapplicable for braiding quantum information. https://arxiv.org/abs/2509.09663

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