Adjust pulse optimal cx two qubit decomposer to avoid RZ(0) #14629
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
In the TwoQubitBasisDecomposer there was a special code path to do pulse optimal decomposition. This code path could occasionally result in a 0 degree angle rz gate being emitted. This would mean the sequence of SX - RZ(0) - SX would be generated which is just an X gate. This commit updates the decomposition to just use an X gate in these cases if they're encountered. This is essentially the same optimization that was done in Qiskit#5937/Qiskit#5827 for the single qubit euler decomposer but this applies it to the pulse optimal 2q decomposition.
|
One or more of the following people are relevant to this code:
|
6 tasks
Pull Request Test Coverage Report for Build 16630282067Warning: This coverage report may be inaccurate.This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.
Details
💛 - Coveralls |
I added tests in: b41e62d |
ShellyGarion
approved these changes
Aug 7, 2025
There was a problem hiding this comment.
thanks for fixing this bug!
and thanks to @t-imamichi for finding it!
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Summary
In the TwoQubitBasisDecomposer there was a special code path to do pulse optimal decomposition. This code path could occasionally result in a 0 degree angle rz gate being emitted. This would mean the sequence of SX - RZ(0) - SX would be generated which is just an X gate. This commit updates the decomposition to just use an X gate in these cases if they're encountered. This is essentially the same optimization that was done in #5937/#5827 for the single qubit euler decomposer but this applies it to the pulse optimal 2q decomposition.
Details and comments