Questions tagged [state-tomography]
For questions about quantum state tomography, that is, the process of fully characterizing a quantum state from experimental measurements.
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Doing Quantum State Tomography on a custom-made gate with Qiskit Pulse
In this simple example I took the Qiskit CX gate, obtained the pulses' schedule and then tried to do Tomography on that. In theory, everything should run smoothly (I think) but I get this "error&...
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Is there a theoretical method to achieve a positive semi-definite density matrix in QST?
The problem of encountering negative eigenvalues in the density matrix during Quantum State Tomography (QST) is well-explained in this Quantum Computing Stack Exchange post.
However, I am seeking ...
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How to do quantum tomography on a subsystem of 2 of 30 qubits in cirq?
I have a 30 qubit system and I need to do quantum tomography on a subsystem of 2 of its qubit. How can I do this in Cirq?
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State tomography in Qiskit on a subset of qubits of real QPU
Could anyone please explain how should I carry out a state tomography on a real device in Qiskit (version 0.43.2)?
I have access to devices with 127 qubits, but I want to perform a simulation using ...
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In what sense does quantum tomography "determine the state prior to the measurements"?
I have come across the term quantum tomography which, according to Wikipedia, is the
[...]process by which a quantum state is reconstructed using measurements on an ensemble of identical quantum ...
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Use qiskit-experiments StateTomographyAnalysis on data previously recorded without qiskit
I would like to use the analysis capabilities of qiskit, i.e. StateTomographyAnalysis of qiskit_experiments on data that were previously measured on a system not ...
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Qiskit experiments state tomography maximum allowed dimension exceeded for pulse gates
I'm trying to run state tomography on a custom pulse gate (currently just a CR(pi/4) pulse) and any attempt to run it on an IBM backend gives a maximum allowed dimension exceeded error. The code runs ...
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Finding the "dual" basis of an overcomplete basis for Quantum State Tomography
This question is related to this stack exchange post: What does the POVM corresponding to single-qubit state tomography look like?
From what I understand, when we are interested in reconstructing a ...
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Why can't we do pure state tomography using interference with a known reference state?
I am new to quantum tomography, and right now I am trying to understand tomography with pure states. It's my understanding if we have the amplitude magnitudes as well as relative phases, we can ...
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Why we use random state to simulate in tomography?
To simulate tomography, we often chose a random state from the Haar measure. But why? If you have any reference for the specific reason, please let me know.
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Error: cannot pickle '_global_parameters' object while performing state tomography with qiskit [closed]
Qiskit version: 0.44.2
Operating system: 64-bit operating system, Windows 10 Pro
...
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Is there a tight operator frame that is also a POVM?
We define the tight operator frame as a set of operators $\{E_i\}_{i=1}^{n}$ satisfying
\begin{equation}
\sum_{i=1}^n \vert \langle \langle E_i \vert X \rangle \rangle \vert^2 = C \Vert V \Vert_2^2, \...
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Global vs local: global density matrix and all the reduced density matrix
I prepare a $n$-qubit quantum state $\sigma$ whose ideal state is $\rho$, then perform state tomography on all the $m$- qubit reduced states. Ideally, I find that all the $m$- qubit reduced states are ...
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Change of basis on a per vector component level
Suppose we have an $n$-qubit quantum state in the computational basis encoded in a classical blackbox function $f(x)$. That is, with $x \in \{0,1\}^n$ we can query $f$ and get the respective ...
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Qiskit experiments on qiskit IBM runtime [duplicate]
I'm trying to perform a state tomography on a quantum circuit using Qiskit experiments. I was able to perform the tomography on the AerSimulator but have still not been able to do the tomography on ...
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