Indefinite causal order for quantum phase estimation with Pauli noise
- URL: http://arxiv.org/abs/2312.02832v1
- Date: Tue, 5 Dec 2023 15:30:31 GMT
- Title: Indefinite causal order for quantum phase estimation with Pauli noise
- Authors: Francois Chapeau-Blondeau
- Abstract summary: Letter explores the recent scheme of switched quantum channels with indefinite causal order applied to the reference metrological task of quantum phase estimation in the presence of noise.
We extend the explorations, previously reported with depolarizing noise and thermal noise, to the class of Pauli noises, important to the qubit and not previously addressed.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This letter further explores the recent scheme of switched quantum channels
with indefinite causal order applied to the reference metrological task of
quantum phase estimation in the presence of noise. We especially extend the
explorations, previously reported with depolarizing noise and thermal noise, to
the class of Pauli noises, important to the qubit and not previously addressed.
Nonstandard capabilities, not accessible with standard quantum phase
estimation, are exhibited and analyzed, with significant properties that are
specific to the Pauli noises, while other properties are found in common with
the depolarizing noise or the thermal noise. The results show that the presence
and the type of quantum noise are both crucial to the determination of the
nonstandard capabilities from the switched channel with indefinite causal
order, with a constructive action of noise reminiscent of stochastic resonance
phenomena. The study contributes to a more comprehensive and systematic
characterization of the roles and specificities of quantum noise in the
operation of the novel devices of switched quantum channels with indefinite
causal order.
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