Fidelity Definition and 11 Threads

I was working on plotting fidelity with time for two quantum states. First I used discrete time( t= 0,1,2,3...etc) to plot my fidelity. I got constant fidelity as 1 with continuous value of time. Next I used discrete set of values ( t=0 °,30 °,60 °,90 °). Here I saw my fidelity decreases and...

$$F =|\langle\psi|\phi \rangle|^2$$ $$|\psi\rangle=|\alpha\rangle|0\rangle$$ $$|\phi\rangle= |\cos(t)\alpha\rangle|i\alpha\sin(t)\rangle$$ $$F=|(|\langle\alpha|\langle 0|)(|\cos(t)\alpha\rangle|i\alpha\sin(t)\rangle)|^2$$ Now simplifying $$\langle\alpha|\cos(t)\alpha\rangle$$...

fidelity for pure state with respect to t=0 is 1. My teacher told me this. But I am not getting this. This is my detailed question the initial state(t=0)##|\psi\rangle=|\alpha\rangle|0\rangle## the final state (t) ##|\chi\rangle= |i\alpha\sin(t)\rangle|cos(t)\alpha\rangle## Fidelity between the...

I have a state |0>|alpha>. Now I want to evolve this state at any time t and find the fidelity between the initial and final states. Any ideas how to do that? My main problem is that I don't know how to evolve this state.

Hi, I'm currently working on showing the relation of quantum fidelity: The quantum “fidelity” between two pure states ρ1 = |ψ1⟩⟨ψ1| and ρ2 = |ψ2⟩⟨ψ2| is given by |⟨ψ1|ψ2⟩|^2. Show that this quantity may be written as Tr(ρ1ρ2). I've been following the wikipedia page on fidelity but can't...

\Homework Statement Show that the Fidelity between one pure state |\Psi\rangle and one arbitrary state \rho is given by F(|\Psi\rangle , \rho)=\sqrt{\langle\Psi|\rho|\Psi\rangle} . Homework Equations The quantum mechanical fidelity is defined as \begin{equation*}...

I want to model a free 2 axis free gyro. I used to have a very detailed model, but cannot find it. It was cross coupled, and included many disturbance torques. All I am looking for is a great source on this topic. Thanks! Mike

Hi, I am trying to read a paper about quantum teleportation and got stuck with calculating the fidelity of the mixed(noisy) channel. Fidelity F := < \Phi^{(-)}_{12} | \rho_{1} \otimes \rho_{23} | \Phi^{(-)}_{12} > where \rho_{1} = | \phi_{1} > < \phi_{1} | and \rho_{23} = t |...

Hello all, I am looking for references to experimentally measured quantum teleporation fidelities. In particular, I am trying to find what is the best fidelity to date. So far I have: Bouwmeester et al., Nature v390, p575 (1997), 0.70±0.3 (with polarization-encoded qubits, before subtracting...

What does it mean by having a quantum fidelity of 0.85?

In general teleportation protocol, an entagled pair is used as a source for teleporting an unknown quantum state and the fidelity, which depends on the source characteristics, is defined as the resemblance of final state to the teleportated state . Suppose we have given a density matrix for an...