Wednesday, December 26, 2012

Quantum Circuit Simulator

All I wanted for Christmas was a quantum circuit simulator. So I wrote one in Javascript using NumericJS.

Check it out:

For a good "Hello world" circuit, here's the diagram for a Bell State...
Try evaluating it yourself and see that |00> or |11> are the only possible outcomes.

You can even compile your own circuits into gates to use in other circuits.

Construct a circuit that transforms a single qubit into |0> with 75% probability and |1> with 25% probability, such as:
Then compile that into gate "F" and use it to create a superposition of |00> with 75% prob and |11> with 25% prob, like this:
Let me know if you find any use out of this. And definitely let me know if you find any bugs.


Arsym said...

Correct me if I'm wrong, but it seems your Pauli-Y gate applies the wrong transformation matrix.
It's doing:
0 1
-1 0

rather than:
0 -i
i 0

Otherwise, it seems like a really solid tool. I'm trying to get the basics of quantum computation, and a simulator should help make things a little more intuitive.

Wybiral said...

Thanks! You are correct, somehow that slipped through the cracks. It's fixed now. I definitely welcome feedback.

I'm working on cleaning up the code some so I can get it all hosted on a version control system so others can review the code and contribute.

ohmygod said...

Can you design one more function to "switch locations of the qubits."? (ex. change the 3rd qubit to be the 2nd qubit, and all the related gates.)