Fidelity-based purity and coherence for quantum states

نویسندگان

چکیده

Purity and coherence of a quantum state are recognized as useful resources for various information processing tasks. In this article, we propose fidelity based valid measure purity monotone establish relationship between them. This formulation is extended to correlation relative measurement. We have also studied the role weak measurement on purity.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Purity and state fidelity of quantum channels

We associate with every quantum channel T acting on a Hilbert space H a pair of Hermitian operators, referred to as “Hamiltonians,” over the symmetric subspace of H^2. The expectation values of these Hamiltonians over symmetric product states give either the purity or the pure-state fidelity of T. This allows us to analytically compute these measures for a wide class of channels, and to identif...

متن کامل

On connection between purity and fidelity of quantum channels

Quantum channels depending on a number of classical control parameters are considered. Assuming the stochastic fluctuations of the control parameters in the small errors limit it is shown that the channel fidelity is equal to the average value of the channel purities calculated in the cases of the control errors presence and absence respectively. The result validity is demonstrated on two parti...

متن کامل

Quantum Fidelity for Arbitrary Gaussian States.

We derive a computable analytical formula for the quantum fidelity between two arbitrary multimode Gaussian states which is simply expressed in terms of their first- and second-order statistical moments. We also show how such a formula can be written in terms of symplectic invariants and used to derive closed forms for a variety of basic quantities and tools, such as the Bures metric, the quant...

متن کامل

Quantum fidelity for degenerate ground states in quantum phase transitions.

Spontaneous symmetry breaking in quantum phase transitions leads to a system having degenerate ground states in its broken-symmetry phase. In order to detect all possible degenerate ground states for a broken-symmetry phase, we introduce a quantum fidelity defined as an overlap measurement between a system ground state and an arbitrary reference state. If a system has N-fold degenerate ground s...

متن کامل

Fidelity and Metrics of quantum states

Fidelity plays an important role in quantum information theory. In this paper, two pairs of metrics of quantum states are introduced based on the Uhlmann-Jozsa fidelity and super-fidelity. They are proved to satisfy the axioms of metrics and return to the Sine metric and Bures metric for the qubit case. The CP expansive property and convex property of the metrics are studied. These metrics have...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: International Journal of Quantum Information

سال: 2022

ISSN: ['0219-7499', '1793-6918']

DOI: https://doi.org/10.1142/s0219749922500162