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  • Open Access

Parity readout in Majorana box qubits from the dispersive to the resonant regime

Sara M. Benjadi and Reinhold Egger*

  • *Contact author: reinhold.egger@uni-duesseldorf.de
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Phys. Rev. B 114, 034503 – Published 6 July, 2026

DOI: https://doi.org/10.1103/j2x7-1h9c

Abstract

We study theoretical models for charge reflectometry and capacitive readout of the Majorana parity degree of freedom in Majorana box qubits, considering decoherence channels within the framework of the Lindblad master equation. Noting that a parity-dependent dynamical susceptibility χz(ω) governs both readout schemes, we provide a general expression for χz(ω) which covers the full crossover from the resonant regime to the off-resonant dispersive regime. In addition, we reexamine previous results which were obtained under a semiclassical factorization assumption. Using three different error measures, we show that this approximation is quantitatively justified in the dispersive regime. In the resonant regime, however, we find deviations from exact reference data, obtained by numerical solution for the steady state of the full Lindblad equation. These deviations are typically of the order of a few percent in the considered error measures.

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Phys. Rev. B 114, 034503– Published 6 July, 2026
  • Received 6 March 2026
  • Revised 10 June 2026
  • Accepted 12 June 2026
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