Today, IonQ announced that it is acquiring the operating assets of Entangled Networks in Toronto, Canada. In addition to expanding its technology base, IonQ will also be expanding its global footprint when the Entangled Networks team joins newly-formed IonQ Canada as part of the deal.

Entangled Networks and its multicore technology fills an important need in IonQ’s future hardware strategy.

IonQ architecture

IonQ uses a trapped-ion quantum computing architecture that is currently centered on linear arrays containing ion qubits. Lasers are used for cooling, creating quantum gates and obtaining readouts.

Today, qubits in IonQ's systems are contained in a single chip called quantum processing units (QPU). The QPUs have multiple linear ion trapping zones with a capacity of about 100 qubits each. IonQ's roadmap not only shows the number of qubits increasing in each QPU, but it also originally had plans to develop the technology needed to connect and network qubits between QPUs using photonic interconnections and optical networking technology.

Now, rather than being developed by IonQ, technology acquired from Entangled Networks will perform the networking function that ties allow the quantum processing functions together. It will play an important role in helping IonQ achieve its ultimate architectural goal of fault-tolerant computations using entangled qubits spanning multiple QPUs scaled to millions of qubits.

The critical nature of networking to IonQ’s future became apparent when the company unveiled a five-year roadmap in 2020. In one of my earlier discussions about the roadmap with Dr. Jungsang Kim, cofounder and CTO of IonQ, he said that IonQ plans to pave the way to modularity by creating smaller, lighter and cheaper QPUs that can be networked together to form a larger computer. “If you want to get to scalable quantum computers," he said, "it has to be modular, no matter what physical qubit architecture we use.” The roadmap calls for modularized QPUs to be networked together using photonic links in a distributed computing setup.

The roadmap includes future development of multi-core QPUs by using multiple compute zones that are capable of scaling to hundreds of physical qubits. The roadmap also anticipates networking multi-core QPUs with other QPUs to form much more powerful quantum machines.

What Entangled Networks brings to the table

Entangled Network's MultiQopt product provides quantum circuit optimization for modular system architectures such as those in development by IonQ. Interconnecting clusters of QPUs isn’t a simple matter of building a fiber network and connecting the devices together. Unlike in classical clusters, the laws of quantum mechanics don’t allow quantum data to be cloned, which is why the configuration must be handled with special hardware, algorithms and programming.

Entangled Networks’ multicore technology and engineering team provide:

• Hardware that consists of the light collection system and the network fabric switch
• Software that contains an algorithm library, optimizing controller and real-time networking control
• Networking expertise

Peter Chapman, IonQ’s president and CEO, summarized the impact of acquiring Entangled Networks to me:

“With today’s acquisition of Entangled Networks, IonQ is one step closer to developing quantum networks capable of tackling the most complex problems of today and tomorrow. While classical supercomputer networks communicate between processors to divide workloads, the goal of our quantum network is to entangle qubits at scale which can lead to larger, more powerful systems used for computation. We are laying the groundwork today for future growth, scalability, and adoption of quantum.”

Wrapping up

In the next few years, IonQ plans to integrate the acquired technology into its quantum computer architecture. Full-scale modular connectivity will provide connections between any qubits inside the system, located across any number of QPUs. The highly scalable architecture should be powerful enough to execute large-scale, complex quantum computational problems, regardless of the structure of the problem.

It should be noted that IonQ has the in-house capability to develop the technology needed to network QPU's together. Over the past decade, Dr. Kim, IonQ cofounder and chief scientist Dr. Christopher Monroe and others have researched the technology needed to network quantum computers together using high-bandwidth connections between QPU devices.

However, acquiring Entangled Networks was the better and more efficient alternative than continuing to develop that technology in-house. Not only did IonQ gain a proven networking technology, it also saved a large amount in development costs and leapfrogged ahead of its original roadmap timelines. IonQ now expects to demonstrate networking between two quantum computers sometime this year.

Networking technology is foundational to IonQ’s scaling goals and future success. Because the acquisition of Entangled Networks gives it the requisite expertise in quantum architecture, plus software and hardware IP, this is a brilliant move by IonQ.