Release 0.22.0

Improvements

• Changed a validation check such that it handles qubit numbers represented as strings. (#184)

• Changed the VQE callback function for SciPy optimizers. (#187)

• Switched from using the deprecated qiskit.circuit.measure.measure function to using a method. (#191)

Bug fixes

• Changed the access to Hamiltonian terms hamiltonian.terms() as a method. (#190)

Contributors

This release contains contributions from (in alphabetical order):

Thomas Bromley, Andrea Mari, Romain Moyard, Antal Száva

Release 0.21.0

New features since last release

• Add two devices for runtime programs and one VQE runtime program solver. (#157)

Improvements

• Improved the login flow when IBMQ tokens are specified as environment variables. (#169)

Documentation

• Improved the quality of docstrings in the library. (#174)

Contributors

This release contains contributions from (in alphabetical order):

Guillermo Alonso-Linaje, Romain Moyard, Tanner Rogalsky, Jay Soni, Antal Száva

Release 0.20.0

New features since last release

• Defined the QiskitDevice.batch_execute method, to allow Qiskit backends to run multiple quantum circuits at the same time. This addition allows submitting batches of circuits to IBMQ e.g., when computing gradients internally. (#156) (#163) (#167)

Improvements

• Added native support for the qml.Identity operation to the Qiskit devices and converters. (#162)

• Added support for the qml.SX operation to the Qiskit devices. (#158)

• Added support for returning job execution times. (#160)

• Added support for Python 3.10. (#170)

Contributors

This release contains contributions from (in alphabetical order):

Guillermo Alonso-Linaje, David Ittah, Romain Moyard, Antal Száva.

Release 0.18.0

Improvements

• Removed adding the verbose option to the arguments passed to the backend such that no warnings are raised. (#151)

Contributors

This release contains contributions from (in alphabetical order):

Christina Lee, Jay Soni, Antal Száva

Release 0.17.0

Improvements

• Removed a validation check for qml.QubitUnitary that existed in the device and
  adjusted a related test case. (#144)

Contributors

This release contains contributions from (in alphabetical order):

Christina Lee, Antal Száva

Release 0.16.0

New features since last release

• Added support for the new qml.Projector observable in PennyLane v0.16 to the Qiskit devices. (#137)

Breaking changes

• Deprecated Python 3.6. (#140)

Improvements

• The plugin can now load Qiskit circuits with more complicated ParameterExpression variables. (#139)

Contributors

This release contains contributions from (in alphabetical order):

Christina Lee, Vincent Wong

Release 0.15.0

Breaking changes

• For compatibility with PennyLane v0.15, the analytic keyword argument has been removed from all devices. Statistics can still be computed analytically by setting shots=None. (#130)

Improvements

• PennyLane-Qiskit has been upgraded to work with Qiskit version 0.25. (#132)

Contributors

This release contains contributions from (in alphabetical order):

Release 0.14.0

Bug fixes

• With the release of Qiskit 0.23.3 gate parameters cannot be arrays. The device now converts arrays to lists. (#126)

• When parsing the IBMQ token and the IBMQ URL, the values passed as keywords take precedence over environment variables. (#121)

• When loading Qiskit circuits to PennyLane templates using load in converter.py, parameters with requires_grad=False are bound to the circuit. The old version bound objects that were not PennyLane Variable's, but that object class is now deprecated. (#127)

Contributors

This release contains contributions from (in alphabetical order):

Christina Lee, Antal Szava

Release 0.13.0

Improvements

• The provided devices are now compatible with Qiskit 0.23.1. (#116)

Bug fixes

• The Aer devices store the noise models correctly. (#114)

Contributors

This release contains contributions from (in alphabetical order):

Olivia Di Matteo, Josh Izaac, Antal Száva

Release 0.12.0

Improvements

• The provided devices are now compatible with Qiskit 0.23. (#112)

Bug fixes

• Removes PySCF from the plugin setup.py and requirements.txt. (#103) (#104)

• Fixed a bug related to extracting differentiable parameters for the Qiskit converter and PennyLane array indexing. (#106)

Contributors

This release contains contributions from (in alphabetical order):

Josh Izaac, Nathan Killoran, Antal Száva