Rachpon Kalra, Principal Quantum Engineering Manager at Microsoft Quantum takes us through the inner workings of a new-gen scientist's world.

Could you tell us a bit about your journey? What are some of your fondest memories from growing up in Bangkok?

I had a great childhood in Bangkok—probably not all that unique for someone from our community. I felt very lucky and privileged. My mom was strong and hardworking; my dad was very intelligent, always reading. My sister lovingly helped me with pretty much everything, and my brother always looked out for me. I loved playing golf with my grandfather. The rest was typical—playing soccer with neighbours, goofing around with cousins, hanging out with friends at school. Just overall good times that I look back on with a lot of gratitude.

What inspired you to pursue a career in quantum physics? What was the training process like?

I didn’t set out to become a quantum physicist. I chose electrical engineering mostly because I enjoyed math and physics, but wanted a stepping stone into a career in finance. But during my undergrad, I ended up interning in Andrea Morello’s quantum research lab—and I got hooked. I’ve been in the field ever since. I completed my PhD, did a postdoc, and eventually joined Microsoft’s quantum team in Sydney. I moved to Microsoft HQ in Redmond earlier this year.Traditionally, a PhD has been essential for this field and is still necessary in academia. But over the past 5–10 years, with the growth of the quantum industry, things have shifted. We’re moving from fundamental research to building quantum machines, and that requires interdisciplinary teams with diverse backgrounds. A PhD still offers a unique and rewarding experience—those years of deep focus are hard to replicate—but now, there are many paths into the field. Some universities even offer undergraduate degrees in quantum engineering—University of New South Wales, my alma mater, was the first in the world to launch such a program. It’ll be interesting to see how this next generation of talent plugs into the industry.

Can you walk us through a typical workday in your life at Microsoft?

The work can be intense, with multiple major projects running in parallel. What keeps it exciting is how varied it is. I might be designing circuits, working directly with hardware, or deep in code or calculations. Not a day goes by without some form of collaboration—discussing ideas, reviewing results, planning next steps, or refining strategy. I’m lucky to be working with a brilliant team, and learning something new every day is one of the most rewarding parts of the job.

What are you currently working on?

My focus is on the hardware that delivers electrical signals to the qubits, essentially controlling them to execute quantum algorithms. Scaling this up to a chip with millions of qubits, which is what’s needed for useful quantum computation, is a massive engineering challenge. These signals are generated externally and must be routed precisely to each qubit, all while operating at temperatures colder than deep space. That creates tough constraints—routing bottlenecks, thermal management, and noise isolation. It’s a fascinating problem that sits at the intersection of physics, engineering, and systems design.

What have you worked on that you’re most proud of?

I’m probably most proud of my recent work, both technically and in terms of career growth. I’ve been entrusted with leading a significant subsystem within the overall hardware stack. It’s been incredibly fulfilling to help push this effort forward and make tangible progress toward our goals.

This is not a career path most people consider. Did you always know this was what you wanted to do? What advice would you give to someone interested in this path?

Not at all—I didn’t know I’d end up here. If you’re considering this path, one piece of advice is to be open to working overseas. This field requires significant funding, so the activity tends to be in countries with strong government investment or major tech companies.

Otherwise, if you’re open to hard work and excited by the idea of solving some of the hardest problems in science and engineering, it can be quite fulfilling.

What’s the most exciting part or biggest takeaway from your career so far? What motivates you?

Right now, I’m deeply motivated by the opportunity in front of me. We have a strong team, a clear engineering roadmap, and the support of a company that believes in long-term innovation. The chance to contribute to something that could be world-changing—that’s what drives me.

Looking back, one big takeaway is that the path here wasn’t always linear. A lot of loosely connected projects and collaborations helped me develop the technical breadth and team relationships that brought me to this point. So, I’d say: embrace the opportunities that come your way, do good work, learn from others, and be a solid team player.

What’s the most exciting or promising development in quantum physics right now?

In quantum computing, we’re seeing breakthroughs across the board. At Microsoft, we announced Majorana 1 earlier this year—a major step in building a topological quantum computer. We’ve also made impressive progress in neutral atom-based platforms through partnerships, showcasing systems with many logical qubits.

Other companies are advancing rapidly as well. Google’s announcement last year of the Willow chip marked a breakthrough for the field, with impressive logical qubit performance in a solid-state system. Diraq, in Australia—where many of my former colleagues now work—is doing pioneering work with CMOS-compatible silicon spin qubits, which could leverage existing semiconductor infrastructure.

These are just a few examples. What’s truly exciting is that advancements are happening across the entire stack, from high-level quantum applications and error correction down to qubit design and control hardware. The field is evolving fast, and we’re at a point where research is turning into engineering reality.

What does your support system look like?

I have an incredibly supportive wife and two amazing boys. My family has always had my back, and I’m fortunate to also have strong support from my in-laws. I’m deeply grateful for all of it.

What’s next for you?

Right now, I’m focused on the work ahead. I’m in a rare and fortunate position—able to contribute meaningfully to the future of quantum computing in a way that would be hard to replicate anywhere else. The work is challenging, but the potential impact is enormous. I’m excited to keep pushing the boundaries and be a part of what comes next.

If you had to explain your job in one sentence, how would you describe it?

I’m part of a team working to build a quantum computer capable of solving some of the world’s great technological challenges.