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arXiv · 2410.22723

Magnetic Field Detection Using a Two-Qubit System Under Noisy Heisenberg Interaction

George Biswas·Sayan Sengupta·Anindya Biswas
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Abstract

We propose a method to design a magnetic field detector using a noisy two-qubit system. The system evolves under a noisy Heisenberg interaction Hamiltonian, and we investigate its behavior by calculating both the $l_1$-norm of quantum coherence and the return probability in the presence and absence of an external magnetic field. We allow for decoherence modeled by quasi-static charge noise in the exchange coupling of the two-qubit system and find that, while the magnetic field does not significantly influence the decoherence process, it introduces a distinct oscillation in the return probability over time. Importantly, the oscillation frequency is directly proportional to the strength of the applied magnetic field, providing a clear signature that can be used for magnetic field detection. These results point towards the feasibility of realizing a practical quantum-based magnetic field detector, with the ability to operate under noisy conditions while maintaining sensitivity to the field strength.

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George Biswas, Sayan Sengupta, Anindya Biswas. 2024-10-30. Magnetic Field Detection Using a Two-Qubit System Under Noisy Heisenberg Interaction. https://doi.org/10.1088/1751-8121%2Fadc887

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