Speaker Spotlight: Quantum Computing with Sebastian Weidt

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Designed for entrepreneurs and anyone on their startup journey, Startup Grind Brighton hosts fascinating fireside chats with local founders to discuss their stories and innovations; events which we’re delighted to be supporters of!

At their recent meetup they were joined by Sebastian Weidt, Founder and CEO of Universal Quantum and the co-creator of the first scalable quantum computer blueprint which invented a pioneering approach to building the life-changing million qubit machine. Combining his expertise in physics and commercial experience, Sebastian has been able to make exciting developments at Universal Quantum, raising millions in funding to date.

We caught up with Sebastian following the event to learn more about his work and career, so if you’re interested in the latest developments of Quantum computing and how Sebastian ‘embraces entanglement’ through his community and company, then read on…


Sebastian Weidt

Tell us a bit about you and the work you do…

Universal Quantum is building the world’s first million qubit quantum computer.  

To achieve this, our unique modular, scalable quantum computer architecture is based on silicon technology where individual modules are connected using ultrafast electric field links to form an architecture that scales. 

In other words, we have designed our quantum computer with scalability in mind from day one. Here’s a full explanation (depending on how technical you want the post to be):

Trapped ion qubits: We use individual charged atoms – ions – as our qubits.

Because the qubits are naturally identical, well isolated from the environment and easily controllable, ‘trapped ion’ quantum computing is the most mature quantum computing technology.

Each ion levitates above the surface of a silicon microchip. Using our design, ions can effectively move around the quantum computer and ‘talk’ to one another. Such all-to-all connectivity is important to unlock the true potential of quantum computing at the million-qubit scale.

This high connectivity may allow more efficient quantum error correction methods to be used. Practically this means fewer qubits can provide the same computational power.

Currently, trapped ion quantum computing also holds world records in almost all the important specifications, such as errors for single / two-qubit quantum gates, connectivity and decoherence time.

Modularity: With a single wafer holding just a few thousand qubits at most, modularity is critical to scale to millions of qubits. One proposed method uses photonic interconnects, with optical fibres connecting different quantum computing modules. The connection speeds of this extremely complicated technology after years of intense research are low and no simple engineering solution is yet available. This, therefore, provides a potentially unsurmountable bottleneck when scaling up.

We take a completely different approach to modularity, using electric field links between adjacent quantum computing modules. As well as using much simpler engineering, our UQ Connect links between modules are orders of magnitude better than alternative techniques.

UQ Connect has achieved a world record connection rate (2424/s) and connection fidelity (>99.999993%) between two trapped ion quantum computer modules.

Our modules also feature a fully connected trapped ion qubit system and integrated qubit control technology. This capitalizes on the wealth of expertise that has come out of the development of the silicon microchips used in conventional computers. So, our modules can be manufactured using established silicon fabrication techniques.

The result is fully integrated self-contained electronic quantum computing modules.

Electronic quantum gates: Trapped ion quantum computers generally use pairs of laser beams aligned to the position of individual ions to execute quantum gates. This requires alignment accuracy to a fraction of the width of a human hair. But imagine trying to align millions of laser beams with such incredible accuracy, while stabilising each one’s power, position and phase – where the slightest deviation stops the quantum computer from working.

We use a much simpler electronic gate technology where a combination of voltages is applied to our microchip.

The best part of this gate scheme is that it doesn’t matter if we have ten or ten million qubits, the number of microwave sources is fixed allowing for dramatically simplified scaling.

A temperature that scales: Many other quantum computing platforms require cooling close to milli-Kelvin temperatures (i.e. absolute zero or -273C). But with such limited cooling power available at that temperature, scaling to millions of qubits is incredibly hard to achieve.

We take a different approach. Our technology only requires cooling to 70K, providing ample cooling power which scales to millions of qubits.

Practical engineering focus: There are many theories about how to build a million-qubit quantum computer, but none of them has a ‘nuts and bolts’ delivery plan – except ours. In 2017 we drafted the first practical blueprint to build a quantum computer with millions of qubits, supported by realistic engineering considerations. It underwent years of scrutiny before publication, and its authors include some of the leading experts from around the world. You can read more about it here.

At Universal Quantum, we don’t just deliver the physics – we also develop truly innovative engineering solutions. Humanity needs a quantum computer with millions of qubits and we’re bringing together a world-leading, truly interdisciplinary team to build exactly that.

There’s also lots of information on our blog – and our a recent post has some nice explanations about our work too.

How do Quantum Computers work?

Quantum computers work in a fundamentally different way to traditional computers and, as a result, they have the potential to tackle real-world problems that would take today’s fastest supercomputers billions of years to solve.

Where traditional computers use “bits”, a quantum computer uses quantum bits or “qubits”. A qubit is a quantum bit. It’s analogous to a traditional computer bit.

But in a classical computer, bits store information as 1s or 0s. In a quantum computer, qubits can exist in multiple states at the same time, a so-called superposition between 1 and 0.

It may sound counterintuitive, but this quantum quirk where particles can co-exist in multiple states unlocks various calculations that simply cannot be done on traditional machines.

But to unlock the potential of quantum computing and see a real impact in society, quantum computers need to get much bigger. Today’s machines have (at most) around 100 qubits and provide useful proofs of concept – but haven’t done anything truly useful for society. We need to reach the million-qubit scale to unlock the full range of applications associated to quantum computing.

Tell us about a moment about that helped define your career.

I’ve was extremely lucky during my PhD and postdoc time with some of the breakthroughs I was working on. This gave me the confidence that useful quantum computers that can change the world can be built on a reasonable timescale and ultimately lead me to the decision to pursue building such machines going forward.

What piece of advice would you give your younger self?

Focus more.

Why is Quantum Computing such an exciting innovation?

From drug discovery to tackling climate change, quantum computers promise to change the world in a wealth of ways while creating value of $450 billion to $850 billion in the next 15 to 30 years – and this figure is probably an underestimate.

Working in quantum computing means working on one of the most incredible challenges, transforming the future of computing to tackle real-world problems that would take today’s fastest supercomputers billions of years to solve.

How are Quantum Computers transforming technology as we know it?

The conversation has shifted from “if” these machines will do something useful for businesses to “when”.  However, it’s difficult to predict as we’re only just starting to understand and identify the many areas these machines will impact.

As quantum computers  scale up drastically, we will see a vast number of applications unlocked (from drug discovery to financial services and climate change), and some of which we cannot begin to imagine yet. 

But it’s important for businesses and the wider public to start interacting with quantum computing now, so they can start to understand and prepare for the potentially significant impact that this disruptive technology will have on the world.

What are some of the most important – or some of your favourite – use cases/scenarios for Quantum Computers?

Drug discovery is a transformative example. Quantum computers could simulate larger, more complex molecules, helping discover and develop new drugs. But we need more qubits to start making an impact in this area.

We’re forming partnerships today with companies who are now exploring how quantum will improve their business and society at large.

Looking at molecular simulations, some recent research from Universal Quantum, for example, discovered that we’d need millions of qubits to simulate the FeMoco molecule. 

FeMoco is responsible for biological nitrogen fixation and a common object of research in quantum computing. The FeMoco molecule is used by nature for converting nitrogen in the air into ammonia, which could then be used for fertilizers. We are currently spending around 2% of the world energy supply on just this process, so a better understanding of the FeMoco molecule could greatly improve efficiency in this field with immense positive impact on world food scarcity and the climate crisis.

Also, we’re starting to understand the way in which quantum computing could tackle climate change on multiple fronts – for example, we’re working with Rolls-Royce and others in a consortium to develop sustainable aviation fuels and next-generation jet engines. That’s just one example. In truth, no one fully understands the breadth of ways quantum computing could help across multiple sectors.

We’re seeing three technologies flood the headlines lately: Web 3.0, the Metaverse, and Quantum Computing. Do they – or could they – interlink?

All three technologies are at different stages of maturity and we’re only just starting to understand what each one could do on an individual basis. Nevertheless, I think it is exciting to think about how they can benefit from each other.

Universal Quantum has now raised significant funding to date – what are your ambitions for the future?

Of course, our long-term goal is to build the world’s first million-qubit quantum computer. Over the next few years, we will deliver world leading quantum computers that our partners around the world can engage with. We will build a large ecosystem with our quantum computers at the center and are particularly keen to partner with our local community from the general public to local government, schools and universities.  

We’re also passionate about democratising this technology to ensure everyone has access, from large corporations to SMBs and individual researchers. To reap the benefits of quantum computing, it’s not about the size of your business but about how early you start to engage with this technology. It may even be that by an SMB moving faster on quantum than their enterprise counterparts, a real long-term competitive advantage could be established.

And finally, Silicon Brighton wouldn’t be here without people like you giving back to the community so… what does the word community mean to you?

A group of people with shared values where we support each other, which matches one of our core values at Universal Quantum to “embrace entanglement”. The use of the word entanglement references the quantum phenomenon that occurs when a group of particles interact with each other. When it comes to community, it’s important to share successes and failures, challenges and concerns, fears and ambitions to support and elevate one another. You can find out more about our core values and how this is helping us nurture our company and community at www.universalquantum.com


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Working hand-in-hand with Brighton’s tech community, we run a range of free meetup groups that cover a broad spectrum of specialist areas; from marketing to programming, product design to data. Check out what’s coming up here and join our community of like-minded individuals in the local tech scene!