W. J. ZENG

I work on research, product and strategy at rigetti quantum computing. I am focused on quantum computer architecture, quantum software and algorithm engineering, and making quantum computing useful.
| twitter | linkedin | arXiv | currently listening | unitary fund |

I am product lead for the forest experimental quantum programming toolkit, including the open source libraries pyquil and grove. I run the unitary fund to support open source quantum programming with grants. My phd thesis at oxford applies abstract methods (mainly from categorical algebra) to the study of quantum algorithms and protocols. Before that I worked with superconducting qubit systems at yale and eth zurich.
If you want to learn more about how to get started with quantum computing, I've written a short introduction, which is part of the documentation for pyQuil.

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Introducing the Unitary Fund: Get $2,000 for your open source quantum computing project [Medium] [unitary.fund] [coverage]

24 June, 2018

I'm starting a new experiment called the Unitary Fund: accepting proposals now to get $2,000 for your open source quantum computing project.

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Programming the world's first quantum computers using Forest [video]

9 May, 2018 at Skillsmatter, London

This talk is an introduction to modern quantum programming. It covers why you might want to program a quantum computer and how you would do so today. The only background assumed is linear algebra and complex numbers at the level of undergraduate computer science.

Quantum computing framework

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The Arrival of Quantum Computing [slides]

19 April, 2018 at Impact.Tech

This talk is an introduction to quantum computing. Part 1 introduces the technology and Part 2 introduces the industry. It covers how you may get involved as a scientist, programmer, entrepreneur, or investor.

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Forest 1.3: Upgraded developer tools, improved stability, and faster execution [blogpost]

22 February, 2017

In December, the team at Rigetti became the first to solve an unsupervised machine learning problem on a gate model quantum computer. We did this by connecting one of our recent superconducting quantum processors, a 19-qubit system, to our software platform, Forest. In the ten weeks since then, researchers have already used Forest to train neural networks, program benchmarking games, and simulate nuclear physics.

Starting today, researchers using Forest will be upgraded to version 1.3, which provides better tools for optimizing and debugging quantum programs. The upgrade also provides greater stability in our quantum processor (QPU), which will let researchers run more powerful quantum programs...

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Easy, Hybrid Quantum Programming with Forest [video] #talk

14 January, 2018
QIP2018, Delft, Netherlands

The first scalable universal quantum computers are now available, such as the 19 qubit processor built by Rigetti Computing. As these devices mature, it is important to consider how best to make use of them. This requires new and applied programming models for quantum computing. In particular, promising near-term algorithms for quantum simulation, optimization, and machine learning require a hybrid quantum/classical programming environment. In this talk, we introduce a freely available open-source environment (Forest) based on a shared-memory intermediate representation ( Quil) that is optimized for this hybrid model. The environment runs through a cloud API with client-side Python libraries that target both superconducting quantum circuit and classical simulation backends. We will share how to get started with Forest, as well as how to do research with example hybrid algorithms using a quantum computer.

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Unsupervised Machine Learning on Rigetti 19Q with Forest 1.2 [blogpost] [arXiv

18 December, 2017

We are excited to share that our team has demonstrated unsupervised machine learning using 19Q, our new 19-qubit general purpose superconducting quantum processor. We did this with a quantum/classical hybrid algorithm for clustering developed at Rigetti...

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Nature Comment: First Quantum Computers Need Smart Software [Nature] [podcast]

13 September, 2017

We outline three developments that are needed over the next five years to ensure that the first quantum computers can be programmed to perform useful tasks. First, developers must think in terms of 'hybrid' approaches that combine classical and quantum processors. For example, at Rigetti we have developed an interface called Quil, which includes a set of basic instructions for managing quantum gates and classical processors and for reading and writing to and from shared memory. Second, researchers and engineers must build and use open-source software for quantum computing applications. Third, scientists need to establish a quantum programming community to nurture an ecosystem of software. This community must be interdisciplinary, inclusive and focused on applications.

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Rigetti Partners with CDL to Drive Quantum Machine Learning [blogpost]

24 August, 2017

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Demonstration of Universal Parametric Entangling Gates on a Multi-Qubit Lattice [arXiv]

20 June, 2017

Demonstration of entangling gates on the Rigetti 8Q processor. This was the first process ever made available through Forest.

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Parametrically-Activated Entangling Gates Using Transmon Qubits [arXiv]

20 June, 2017

Parametric entangling gates developed for the Rigetti 8Q processor.

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Architectures for Hybrid Quantum/Classical Computing [slides] #talk

22 May, 2017

Quantum Computing Institute Seminar, Oak Ridge National Lab, TN
In this talk, we introduce an open-source environment (Forest) based on a shared-memory intermediate representation (Quil). The environment runs through a cloud API with client-side Python libraries that can target both superconducting quantum circuit and classical simulation backends. We discuss the programming model and implementations of the Quantum Approximate Optimization Algorithm in this environment.

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A Practical Quantum Programming Workshop [video] #talk

16 January, 2017
QIP2017, Seattle, WA

This was the original QIP workshop that introduced Forest, an open source quantum programming toolkit targeting near-term applications and devices. It is based on the Quil instruction set and introduces the libraries pyQuil and grove.

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Quantum Programming on Near-term Devices [slides] #talk

29 November, 2016

Simons Institute, University of Berkeley, CA - Invited talk at the Semantics, Formal Reasoning, and Tools for Quantum Programming MURI Review.

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A Functional Architecture for Scalable Quantum Computing [IEEE] [direct download]

17 October, 2016

We describe a scalable functional architecture for superconducting quantum computation, based on a planar lattice of transmon and fluxonium qubits, parametric amplifiers, and a novel fast DC controlled two-qubit gate.

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A Practical Quantum Instruction Set Architecture [arXiv] [blogpost]

11 August, 2016

We introduce an abstract machine architecture for classical/quantum computations---including compilation---along with a quantum instruction language called Quil for explicitly writing these computations. With this formalism, we discuss concrete implementations of the machine and non-trivial algorithms targeting them. The introduction of this machine dovetails with ongoing development of quantum computing technology, and makes possible portable descriptions of recent classical/quantum algorithms. This instruction set architecture is the basis for the quantum programming platform Forest.

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Quantum Algorithms for Compositional Natural Language Processing [EPTCS]

4 August, 2016

We introduce an algorithm for compositional natural language processing that can be accelerated quadratically by quantum computation.

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High-threshold decoding algorithms for the gauge color code [slides] #talk

16 March, 2016

Baltimore, MD - APS March Meeting 2016
Gauge color codes are particularly interesting quantum error correcting codes because the admit a universal logical gate set through gauge fixing. We study the threshold of gauge color codes using Markov-chain Monte Carlo decoding.

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The Abstract Structure of Quantum Algorithms [Oxford Thesis]

26 December, 2015

Quantum information brings together theories of physics and computer science. This synthesis challenges the basic intuitions of both fields. In this thesis, we show that adopting a unified and general language for process theories advances foundations and practical applications of quantum information. Results include new blackbox quantum algorithms, generalized quantum secret sharing and contextuality protocols, a categorical analysis of the Fourier transform in process theories, and an algorithm for natural language processing with a quantum computer. The main mathematical tools used in this thesis are group theory (esp. Fourier theory on finite groups), monoidal category theory, and categorical algebra.

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Contextuality and the Weak Axiom in the Theory of Choice [Proc. Quantum Inter.]

23 November, 2015

This work applies contextuality (a mathematical formalism developed in quantum mechanics) to models of social choice theory. In essence, we mathematically characterize when it makes sense to consider the choices of a group as composed of individual choices, finding an interesting link between no-signaling theories and the weak axiom of revealed preference.

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The Quantum Software Challenge [Medium]

19 October, 2015

What software engineers should know about quantum computing...

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Diagrammatic Methods for the Specifcation and Verifcation of Quantum Algorithms [slides] #talk

9 June, 2015

Institute for Quantum Computing, University of Waterloo - Quantum Programming and Circuits Workshop

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sticks [Medium] #fiction

7 Feburary, 2015

In earlier years, we would hold small angled sticks...

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see [Medium] #fiction

27 January, 2015

See that little in the weathered man’s life could match the intensity, the panting rhythms, the speed of the sled dogs...

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Abstract structure of unitary oracles for quantum algorithms [slides] [video] [paper] #talk

6 June, 2014
Kyoto, Japan - Quantum Physics and Logic ( QPL ) 2014

This paper studies the categorical structure of quantum algorithms with oracles to develop a new algorithm for the deterministic identification of group homomorphisms into abelian groups. We also discuss an application to the categorical theory of signal-flow networks.

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A Subtle Introduction to Category Theory [notes]

Spring, 2013

Some playful notes and riffs on monoidal category theory. Very much a WIP.

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For Sale [link]

16 August, 2013

A microfiction.

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Rowing

I've done my fair share of river batting.

The Oxford-Cambridge Boat Race 2012 [wiki]
  Oxford Prepares Videos: [1] [2] [3] [4] [5] [6] [Epilogue] [Race Highlights]
  Media: [NYT] [theguardian]

IRA National Championships 2011 w/ Yale Lightweight crew [video]

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Tweets by @wjzeng

Enjoy. Thanks for coming by.