Give FakeOpenPulse2Q qubit T2 times and readout errors #7425
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It had some properties, but didn't have the full set. This meant that things like the T2 times weren't filled in by the defaults, so trying to access the T2 times of any qubits was an error. The values chosen here are unimportant; in this case they were simply drawn from a linear regression of all T1 times against T2 times. The readout errors were just a reasonable value.
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It had some properties, but didn't have the full set. This meant that things like the T2 times weren't filled in by the defaults, so trying to access the T2 times of any qubits was an error. The values chosen here are unimportant; in this case they were simply drawn from a linear regression of all T1 times against T2 times. The readout errors were just a reasonable value. Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> (cherry picked from commit 2867f20)
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It had some properties, but didn't have the full set. This meant that things like the T2 times weren't filled in by the defaults, so trying to access the T2 times of any qubits was an error. The values chosen here are unimportant; in this case they were simply drawn from a linear regression of all T1 times against T2 times. The readout errors were just a reasonable value. Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> (cherry picked from commit 2867f20) Co-authored-by: Jake Lishman <jake.lishman@ibm.com>
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Summary
It had some properties, but didn't have the full set. This meant that
things like the T2 times weren't filled in by the defaults, so trying to
access the T2 times of any qubits was an error. The values chosen here
are unimportant; in this case they were simply drawn from a linear
regression of all T1 times against T2 times. The readout errors were
just a reasonable value.
Details and comments
Aer 0.10's noise model tries to read T1 and T2 times for all qubits, which causes test failures for us due to the missing properties. I would have expected that a missing property would return
0, but that's probably pretty dangerous behaviour and I don't want to mess around in theBackendPropertiesclass much because I don't know the context. Instead I've just givenFakeOpenPulse2qsome arbitrary T2 times and readout errors, since it feels like it should know those anyway.We can also patch the Aer
NoiseModelto treat missing T1/T2 times as 0.