Questions tagged [entanglement-negativity]
For questions about the entanglement measure derived from the PPT separability criterion.
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Are there quantum algorithms to estimate the partial transpose?
The entanglement negativity and the positive partial-transpose criteria play important roles in quantifying the amount of entanglement for mixed states. Yet, because these measures generally involve ...
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What is the maximum and minimum value of logarithmic negativity measured for bi-party entanglement?
I have calculated logrithmic negativity for my biparty entangled system in a superconducting circuit. The negativity gives a sine curve where maximum value comes out to be 4 and minimum 0.5. Now, how ...
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Is there an identity for the partial transpose of a product of operators?
The partial transpose of an operator $M$ with respect to subsystem $A$ is given by
$$
M^{T_A} := \left(\sum_{abcd} M^{ab}_{cd} \underbrace{|a\rangle \langle b| }_{A}\otimes \underbrace{|c \rangle \...
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What is the logarithmic Negativity of the Werner state? [closed]
What is the Logarithmic Negativity of the Werner state
$$\rho_w = p|\Psi^-\rangle\langle\Psi^-|+\frac{1-p}{4}I_4$$
where $|\Psi^-\rangle = \frac{1}{\sqrt{2}}(|10\rangle-|01\rangle)$?
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How do I calculate Logarithmic Negativity for the given bipartite state?
How can I calculate Logarithmic Negativity for the given state?
$\rho = \frac{1}{2} |0\rangle \langle0| \otimes |+\rangle \langle+| +\frac{1}{2} |+\rangle \langle+| \otimes |1\rangle \langle1| $
user14749
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In a bipartite system $AB$, why does the entanglement negativity $\mathcal{N}(\rho^{T_A})$ measure the entanglement between $A$ and $B$?
Consider a system composed of two subsystems $A$ and $B$ living in $\mathcal{H}=\mathcal{H}_A \otimes \mathcal{H}_B$. The density matrix of the system $AB$ is defined to be $\rho$. The entanglement ...
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What is the deep physical reason behind the existence of bound entanglement? [closed]
In Quantum Information processing, we can extract entanglement from $n$-copies of a weakly entangled state to produce a fully or highly entangled states in $d$-dimensions, using the known distillation ...
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Compute the negativity of maximally entangled bipartite states
The entanglement negativity $\mathcal N(\rho)$ of a (bipartite) state $\rho$ is defined as the absolute value of the sum of the negative eigenvalues of the partial transpose of a state, or ...
glS♦
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Why does the entanglement negativity equal (in magnitude) the sum of the negative eigenvalues?
The entanglement negativity, introduced in (Vidal and Werner 2002), is defined as
$$\mathcal N(\rho) \equiv \frac{\|\rho^{T_B}\|_1-1}{2}.$$
It is mentioned there that this equals the sum of the ...
glS♦
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