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Duttatreya

Publications and source records attributed to Duttatreya.

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Improved coherence time of a non-Hermitian qubit in a $\mathcal{PT}$-symmetric Environment

Quantum computing's potential for exponential speedup is fundamentally limited by decoherence, a phenomenon arising from environmental interactions. Non-Hermitian quantum mechanics, particularly $PT$-symmetric systems, offers a novel framework for extending coherence times. This study examines a qubit's coherence under non-Hermitian $PT$-symmetric dynamics, highlighting significantly enhanced coherence times compared to Hermitian setups. The effect is especially pronounced when both the system and environment exhibit $PT$-symmetry. Interestingly, greater environmental non-Hermiticity correlates with extended coherence, contrary to traditional expectations. These findings point to promising strategies for managing decoherence, which could significantly advance approaches to quantum information processing.

quant-ph

Enhanced quantum phase estimation with $q$-deformed nonideal nonclassical light

We investigate quantum phase estimation in a Mach-Zehnder interferometer using q-deformed photon states, including q-coherent and q-cat states, which model realistic deviations from ideal light sources. By deriving closed-form photon count likelihoods via the Jordan-Schwinger mapping, we compute the quantum and classical Fisher information and perform Bayesian inference on simulated detector data. Our results show that photon counting remains an optimal measurement strategy even for deformed states, with classical and quantum Fisher information in exact agreement. Furthermore, the phase sensitivity improves with increasing q-deformation, indicating enhanced metrological performance driven by nonclassical photon statistics. These findings highlight the utility of q-deformed states in quantum sensing.

quant-ph