How to check if a matrix is a valid density matrix?
2018年6月14日 · Since the $|\psi_j\rangle \langle\psi_j|$ are Hermitian, and since probabilities are real numbers, the density matrix is Hermitian. Since probabilities are all either zero or positive, …
Produce a quantum state with its density matrix an identity matrix …
2020年11月16日 · $\begingroup$ Your concern makes sense, but an identity density matrix is not all I need. Another quantum register is also required and there is additional unitaries act …
linear algebra - How to calculate the log of a density matrix ...
2022年12月23日 · Note that I wrote a matrix because in general it may not be uniquely defined. Recall the definition of $\exp(L)$: $$\exp(L)=\sum_{n=0}^{+\infty}\frac{L^n}{n!}$$ For a …
density matrix - How to calculate the Schmidt decomposition of a …
2024年5月21日 · The correct approach to get the Schmidt vectors would be to compute the eigendecomposition of $\Psi\Psi^\dagger$ and $\Psi^\dagger\Psi$, with $\Psi$ the original …
Qiskit: density matrix after measurement - Quantum Computing …
2023年2月24日 · It's more or less my first day working with qiskit and hearing about density matrix, so sorry if the question doesn't make sense. Ideally, I want to have the following …
What's an easy way to determine a local density matrix?
2019年7月24日 · For calculating a local density matrix or in other words taking a partial trace has a neat trick (IMHO): The Trick: Write the state given in density matrix form, if not already. …
density matrix - Does the trace distance between these averages …
2024年10月17日 · density-matrix; Share. Improve this question. Follow edited Oct 17, 2024 at 22:02. glS ♦. 27k 6 6 gold ...
programming - How to code density matrix in python? - Quantum …
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A proof that 4 ≥ ∞ when using the Quantum One-Time Pad
2024年12月8日 · $\begingroup$ @MarkSpinelli That the mixed-state density matrix representing the distribution of QOTP ciphertexts (over uniformly-distributed keys) for any given pure state …
How to show a density matrix is in a pure/mixed state?
2019年4月22日 · First, the example that you give is not a density matrix (they must have trace 1). Second, you’re asking how to go from the matrix into an operator representation that is not …