psitae
  • Member for 3 years, 9 months
  • Last seen this week
  • Shanghai, China
How is a physical qubit measured and how is the result interpreted?
Accepted answer
5 votes

What follows turned out to be a rather technical explanation, so I'll start with the main point: The qubit state can change the resonator's state, and the resonator's state can be easily measured only ...

View answer
State of the art of SAT on a quantum computer
Accepted answer
4 votes

This is an open question. People who try to prove $\text{BQP} = \text{NP}$ usually use the SAT formulation, in my experience. But we don't know of any algorithm that addresses the structure of the SAT ...

View answer
How many classical bits are needed to represent a qubit?
3 votes

It takes an infinite amount of information to specify the state of a qubit. That's for the reason you said: those two angles to specify the point on the Bloch sphere are continuous, and that means you ...

View answer
How to get started with the Alibaba Cloud Quantum Computing Service?
Accepted answer
3 votes

http://quantumcomputer.ac.cn They really need to get their act together and make sure it's on the first page of Google. I had to go way into uncharted territory to find this. (Like, not the first ...

View answer
Why don't qubits continuously rotate in the $z$ direction due to free time evolution?
2 votes

They are always rotating in the lab reference frame, but most quantum algorithms take a rotating reference frame to simply things, so that a z rotation only happens when you want it to. The rotating ...

View answer
Measuring qubits in QuTiP
2 votes

Here. Scroll down to the stochastic solver, and you'll find an attribute for storing measurements. It's certainly not the emphasis of the package, as cnada pointed out, but it's there.

View answer
What is the probability of a single qubit state lying over the surface of Bloch sphere?
1 votes

For a single qubit that's in a pure state (no decoherence) the probability that the state is somewhere on the surface of the sphere is 1. You don't need to measure this. If you're going to do a POVM ...

View answer
Numerical quantum state tomography simulator
Accepted answer
0 votes

To me the best choice is clearly qutip, a quantum computing simulator based in Python. It's free, and it has good documentation. Let us know if you have any other queries beyond asking which ...

View answer