T1, T2 not mapped to IBMQubitProperties

[dieris]

Information

• qiskit-ibm-provider version: main
• Python version: 3.11
• Operating system: Windows

What is the current behavior?

The backend properties T1, T2 are not correctly mapped to the IBMQubitProperties t1, t2 in _decode_qubit_properties

Steps to reproduce the problem

For any backend_name,

from qiskit_ibm_provider import IBMProvider
backend =  provider.get_backend(backend_name)
backend.target.qubit_properties()

returns e.g.

[IBMQubitProperties(t1=None, t2=None, frequency=4883140335.692719, anharmonicity=-344828063.1378064),
...

What is the expected behavior?

t1 and t2 should be populated from the corresponding T1, T2 values

Suggested solutions

If we want to maintain lowercase t1, t2, as IBMQubitProperties, add .lower() to

qiskit-ibm-provider/qiskit_ibm_provider/utils/json_decoder.py

Line 368 in cf6d062

name = spec["name"]