Qubit-Neutral: Qblox Builds Quantum Control Stack
Overview
Recorded live at the APS Global Quantum Summit in Anaheim, California in March 2025
Quantum hardware isn’t quite ready for server racks in data centers, but that is the vision driving engineers at Qblox. This Dutch company builds control electronics for all qubit modalities. In this episode of The Quantum Spin by HKA, Niels Bultink, co-founder and CEO of Qblox, explains how he built a team that helps researchers and entrepreneurs get the highest performance out of quantum hardware. He also describes how the quantum ecosystem in the Netherlands grew out of strong academic institutions and why collaboration is a key value for the sector.
00:00 Introduction to Quantum Spin Podcast
00:36 Interview with Niels Bultink, CEO of Qblox
00:42 Understanding Qubit Control Electronics
02:11 Challenges and Opportunities in Quantum Technology
03:55 Qblox’s Role in the Quantum Ecosystem
07:59 Future of Quantum Computing and Industry Trends
13:46 Closing Remarks and Contact Information
Niels Bultink is the CEO and co-founder of Qblox, a leading provider of scalable quantum control stacks. Niels has a PhD from TU Delft in quantum information processing. He specializes in controlling quantum computers, performing the first feedback on solid-state qubits in 2012. His PhD research with Leonardo DiCarlo at TU Delft has led to more than ten scientific publications centred around fault-tolerant quantum computing with superconducting circuits. With Qblox’s industrialized generation of control stacks, and building and scaling Qblox, Niels is paving the way for quantum computer integrators worldwide to reach practical applications in quantum computing.
Transcript
[00:00:00] Veronica: Hello, I’m Veronica Combs, and this is the Quantum Spin by HKA. For season four, we decided to do something a little different. In March, we attended the APS Global Physics Summit in Anaheim, California. We took advantage of this amazing event to talk to the leaders in academia, industry, as well as the creative folks who helped make the event such a compelling experience.
[00:00:23] I hope you enjoy these conversations that really reflect what’s happening in the industry right now.
[00:00:32] Today I’m talking with Niels Bultink, the CEO of Qblox. Thank you so much for being with us today.
[00:00:40] Niels: Thanks Veronica. Really great to be here.
[00:00:41] Veronica: So Qblox makes qubit control electronics. How does that fit into the whole grand scheme of quantum hardware?
[00:00:49] Niels: So, yeah many folks, many companies and universities around the world are aiming for quantum technology. They want to bring the smaller scale physics to become really useful when it comes to many forms of technology communication or computing power.
[00:01:05] And, it’s important to realize that doing that requires many forms of technology to really work well together. So at the bottom it starts with the quantum bits themselves. So the physical layer, the quantum chips. And then around that you need a whole framework of technology starting with the cryogenics.
[00:01:22] So the environment that cools down the quantum bed that creates an ultra-high vacuum to screen it from the bombardment of noise around us that we have at room temperature today here, although we don’t notice that, but qubits do. Yes. And then you need a control system, that’s what we make to control those quantum bits to send signals that create quantum operations and also to read out the quantum bits to understand what the outcome of the algorithm is. And that’s what we specialize in with Qblox.
[00:01:51] Veronica: Yes. I think we spend a lot of time talking about modality, but once you’ve picked a modality, that’s just the beginning of your construction process.
[00:01:57] Right. Because you do need all the control electronics to take care of the qubits and to get them to tell you what you want to know.
[00:02:02] Niels: Exactly, yes.
[00:02:04] Veronica: And there’s so many subsystems, right? It’s a complex system that works together to provide that control.
[00:02:09] Is that right?
[00:02:10] Niels: That’s correct. Many of the developers out there are really focusing on the quantum chips and there’s a whole range of different qubit modalities, and that’s really great because it’s still unclear which of the quantum bits will win. They each have their own advantages and disadvantages.
[00:02:25] Other parts of the stack actually have a bit more opportunity for focusing and really making one system that can control the different modalities out there. So that’s what we saw in 2017-18 when we launched Qblox, to really focus on those other layers so that the rest of the world can really do their job in making better and bigger quantum.
[00:02:46] Veronica: Right. So your components help go up the abstraction layer, is that the right way to think about it?
[00:02:52] Niels: Correct. Yes. And allows others to develop quantum bits faster.
[00:02:55] Veronica: And so your system is qubit neutral, right? So trapped ion superconducting, how do you, how does that work? Making it qubit neutral?
[00:03:03] Niels: Yeah. It’s more that nature has invented it this way the way those quantum bits work internally, like it’s either encoded in some levels of an atom in the case of ions or it’s an artificially made atom in superconducting circuits.
[00:03:17] There are very different aspects. The frequency ranges they work at can be very different optical or microwave regimes. But when down to the control levels it is actually quite similar and that’s an advantage. And we use that to make a system that is very widely applicable.
[00:03:33] So with relatively minor tweaking of the outputs to accommodate for those different frequency ranges, so to make our system work with lasers, for instance, for optically trustable qubits or directly control quantum bits in superconducting circuits. It’s quite, no, I wouldn’t say easy, but it’s doable to make it very functional and easy to integrate with those many different qubit styles.
[00:03:54] Veronica: Right. And you’re a co-founder of Qblox and your background is applied physics. So you’ve been yes, focused on this for a while.
[00:03:59] Niels: I come from the trenches indeed. So I’ve been at the APS March meeting since 2013 or 14. I have only missed it once due to Covid. But yeah, I was a quantum researcher in superconducting qubits at QuTech in Delft and there I was in the labs making small quantum air correction experiments work with superconducting qubits. Also doing the first feedback on quantum bits back in 2012.
[00:04:26] Those projects developed more and more towards needing more quantum bits and needing more complex control systems. Back then we worked with other companies and governmental institutes to develop those first sort of prototype quantum pure play, quantum dedicated electronics.
[00:04:42] We spun it out into Qblox. So, yeah, one of the first really quantum-oriented electronics companies with 140 people over 150 customers around the world that all work with those systems. So it has become really a community of of users and people that develop the systems.
[00:04:59] Veronica: Yeah. So you must have a range of customers.
[00:05:02] Niels: Correct. It spreads over qubit modalities but also when it comes to different entities. So we have many academic labs, governmental labs, but also the many scale up and startups and also the industrial players that use our systems.
[00:05:16] So some to develop on a small scale, better quantum bits. So really focusing on the quality but also some of the more engineer-oriented projects. The companies that focus on making tens and hundreds of qubit systems, we also work with those.
[00:05:30] Veronica: So I’ve heard a couple folks say that quantum computing, quantum hardware is mostly a matter of engineering now. Do you think that’s true? We’ve solved some of the physics problems we’ve got? We’ve, I’m always, I like, I’m not sure, but that’s true or not. I always like to get a variety of opinions.
[00:05:45] Niels: I slightly disagree with that. I think it is really a very big project involving a lot of scientific challenges and engineering challenges.
[00:05:53] So I think the role for academia and governmental labs has certainly not stopped. We need much better quantum bits than what we have today. Both when it comes to quality and skill. There are many engineering and scientific challenges, so, right, I think actually the way the community coming together here is really how it should be with all of those bringing up different ideas from different angles and and showing how we can move forward.
[00:06:17] Veronica: Right. So are your teams organized around modality or is one group focused on a specific challenge with a quantum computer? How does that part of your company work?
[00:06:26] Niels: It’s an interesting question. Most of the parts companies are making products. So it’s different modules that have control or readout tasks for quantum bits. But then those very modules are used in the different qubit modalities. Another part of the company is organized around different types of quantum bits to understand the users, what do the users need, how do they use the equipment, how can we provide the right software interface for those users to understand those markets and customers better.
[00:06:55] So it’s both. Some are organized around the hardware and the products and others are focused around understanding the customer and how we can serve them better.
[00:07:03] Veronica: I have to say, your website is very elegant. Good job marketing. And it looks like a server rack. Is that the long term vision, that you’ll have components that people can use in their quantum computing center?
[00:07:15] Niels: Indeed. From the beginning we were the first one to make more integrated, denser systems. It has a couple of practical reasons because quantum chips get larger, but also there’s an important movement from academia towards more HPC environments. And there we already have a few of those quantum systems with our control integrated in HPC centers, like in the Barcelona Supercomputer Center, that was recently a lot in the news. And those HPC environments ask different form factors but also the hardware and software integration into those environments, and that’s why we always develop the system in a very dense and more HPC ready way.
[00:07:58] Veronica: For a while we were talking about quantum advantage and you know, thinking of quantum computers in isolation, but more recently there’s been a lot more discussion of hybrid environments, and HPC, AI and quantum computing. Is that how you think of the next phase of the industry, that combination of all those different technologies?
[00:08:15] Niels: Yeah, definitely indeed. For us it starts with integrating into HPC environments so that the connection between quantum bits and classical resources is as tight and fast and seamlessly as possible.
[00:08:27] That opens this whole field of AI and HPC or classical computing resources to work well with quantum. So we are creating this connection and it opens quantum resources for an entire new scientific field to use quantum resources for AI purposes, for instance.
[00:08:43] Veronica: The Netherlands has quite a robust quantum ecosystem. Can you tell me a little bit about that?
[00:08:48] Niels: So it started out with a few really core academic institutes like Q Tech, that where I stem from. TU Delft and TNO collaboration which is always one of the top five, top 10 institutes around the world in terms of scientific output.
[00:09:04] That slowly migrated into adopting more engineering challenges. And those engineering challenges have often or those solutions have often created the grounds for spin out companies. So Qblox, but also other companies like Delft Circuits, QuantWare, and QphoX, that are turning those scientific solutions, engineering solutions into products.
[00:09:25] So it’s a very natural migration from science towards engineering, but also now creates a really good hub for all those entities to work together. So it’s a very collaborative environment in the Netherlands and that’s really good for us to be and, uh, yes, work together.
[00:09:41] Veronica: Yes, at Qblox seems to prioritize that camaraderie and collaboration.
[00:09:44] Niels: Indeed. Not just in the Netherlands, also in Europe, in the US we have many forms of collaboration. Indeed. Yeah.
[00:09:51] Veronica: So, I’m curious about your perspective on the industry in general as a CEO and someone who’s so involved with so many different companies. Are there modalities that you’re tracking or developments or what, how are you thinking about the industry today?
[00:10:04] Niels: An important trend that I see is this trend of it going from the idea that one entity alone develops the whole stack. It goes much more into, to become a value chain. So different entities really focus on one layer in the stack and do that the best in the world instead of everyone trying to do everything by themselves.
[00:10:22] That’s a trend that has been going on and is becoming stronger and stronger now. Also on the software side with many companies creating value there. That’s one very important trend that I think is also important to move the field forward. And another one is the move towards HPC centers and to involve AI and all those disciplines.
[00:10:41] Veronica: Yes. And there’s such an investment in those resources already, right? We have supercomputing centers and to be able to build on those and integrate quantum and AI is a really important way to move forward, it seems indeed.
[00:10:51] Niels: Correct.
[00:10:53] Veronica: So what does the year hold for Qblox? Are you working on new products or I know that you’ve grown so much lately over the last couple years.
[00:11:00] Niels: Indeed. Yeah. We’re on a very fast growth path. So first, at APS here, it’s always exciting to be here. We always create a lot of product launches. We have launched two products: the QSM, for very stable signals, as well as the QRC, which is a qubit readout and control module. It’s denser and better than what we have had so far. So it’s really exciting to launch those products as well as on the software side to provide better solutions for integrating our systems for the different qubit modalities.
[00:11:30] Veronica: And do you have any advice for people looking to get into the quantum industry, either as a physicist or a software engineer?
[00:11:36] Niels: Of course knock on the Qblox door and yes it’s a really exciting field to be in. So I really encourage people to do PhDs if they are in the scientific orientation or if they like engineering to join companies like ours.
[00:11:49] It’s a really exciting field to be in. Companies have extremely motivated teams very intrinsically motivated to bring exciting technology to the market and develop it.
[00:11:59] Veronica: Yes. I think a sense of curiosity and the willingness to learn is another really key part of being in the quantum industry.
[00:12:06] Niels: Yeah. And doing that with like-minded people is very thrilling.
[00:12:09] Veronica: Yeah, the energy and just the excitement here at the conference has been great, to see so many people working together and the level of enthusiasm for the work and the discovery.
[00:12:17] Folks have been talking so much lately about quantum advantage and when are we going to outperform classical? And I think you know, if we can leap beyond that debate and just think about once you get a fault tolerant quantum computer, is there a problem that you personally are interested in and would like to take on?
[00:12:30] Niels: So, my dream application? Yes, exactly. I’m very hopeful that quantum technology will solve many of humankind’s most difficult problems. One area I’m particularly interested in is to provide better solutions for the energy issues and the environmental issues.
[00:12:46] So if we can create better materials for solar panels or if we can realize nuclear fusion reactors, that would mean one of the biggest issues in the world would be solved, right? It’s not going to happen next year, but maybe in the coming 20 years, that can be reached and that would be wonderful.
[00:13:05] Veronica: And I think even small gains. I think people don’t understand how powerful that could be. Right? Like a battery that’s even 5% better or chemical reactions that we understand just a little bit more would be a big difference for improving solar panels or building new batteries. So, that’s the perspective I take on the “when are we going to get advantage,” you know, there’s gradual improvement over time, which is no small thing.
[00:13:24] Niels: Indeed, In the NISQ era, it’s often talked about. The thousands of quantum bit systems can already do solutions that classical computers cannot do. But it’s also important to understand that the real big economic value and the real big solutions will come from fault tolerant quantum computing, and it means millions of quantum bits, so stay tuned.
[00:13:44] Veronica: Yes. Thank you so much for taking time to talk with us today. I really appreciate it.
[00:13:49] Niels: Thank you very much, Veronica. [00:13:49]
Host Veronica Combs is a quantum tech editor, writer and PR professional. She manages public relations for quantum computing and tech clients as an account manager with HKA Marketing Communications, the #1 agency in quantum tech PR. You can find them on X, formerly known as Twitter, @HKA_PR. Veronica joined HKA from TechRepublic, where she was a senior writer. She has covered technology, healthcare and business strategy for more than 10 years. If you’d like to be on the podcast yourself, you can reach her on LinkedIn, Veronica Combs, or you can go to the HKA website and share your suggestion via the Contact Us page.
April 24, 2025
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