Cirq V0.14 release

[Michael Broughton]

Hi Cirq Users,

We have just released Cirq v0.14.0.

Highlights of this release include:

Transformers

Revamped and deprecated many of the old and buggy optimizers found in cirq.optimizers with new cirq.transformer implementations. New transformers have well defined functionality with CircuitOperations and should be easier to use overall.

Classical Control

Cirq now has support for classical control in NiSQ relevant regimes. Classically controlled operations and measurement feedforward operations are supported. Extension into arbitrary classical logic on top of this is not on the immediate roadmap.

Devices

Devices have undergone a rework. Functionality to: attach a device to a circuit, use a device as a means to decompose a circuit, and exploration related functions have been removed. Devices now validate circuits and carry a DeviceMetaData property if more description of the device is needed.

Misc

In addition to the larger changes mentioned above, this release also includes new experiment utilities for characterizing device readout errors with cirq.measure_confusion_matrix. The cirq.decompose function contract has now been tightened to return a circuit containing just X,Y,Z,C*Z gates (assuming a decomposition is possible). Repeated measurement keys will now store temporal measurements (where previously they would be disallowed). New simulation techniques based on (https://arxiv.org/abs/2112.08499) and more.

You can view a complete list of features, fixes and breaks for this release here.

To install this upgrade run `pip install cirq==0.14.0`

Thank you to all our contributors for this release:

Abraham Asfaw, Adam Zalcman, Aleksandr Pak, Alex McNamara, Animesh Sinha, Anna Nachesa, Antoine (Tony) Bruguier, augustehirth, Bicheng Ying, Cheng Xing, Dave Bacon, Dax Fohl, dependabot[bot], Doug Strain, Evan Peters, Freyam Mehta, Hosseinberg, Ilja Livenson, Jintao YU, Jon Donovan, Matthew Harrigan, Matthew Neeley, Michael A. Perlin, Michael Broughton, Nathanael Thompson, Orion Martin, Pavol Juhas, Tanuj Khattar, Victory Omole, Zachary Crockett

Cheers,

Michael