By Elizabeth Medina

March 9, 2026

The Harvard Blocheads, a team of 5 Harvard undergraduates, wins first place in their challenge at the 2025 International Quantum Circuit.

Anmay Gupta ’27, Emmanuel Rassou ’27, Hugo Mackay ’27, Tarun Sasirekha ’27, and Jonathan Waldorf ’28 first joined forces during iQuHACK, MIT’s annual quantum computing hackathon.

Whereas traditional hackathons, like HackHarvard, are often about “creating a new project,” quantum hackathons often consist of “solving some specific problem or developing a more complete algorithm for one,” explained Gupta. At iQuHACK, these problems were created by the hackathon’s industry sponsors and teams applied for whichever challenges they thought were the most interesting. For the Blocheads, the most alluring challenge was posed by quantum computing company IonQ. The goal? Solve the classical computer science problem “MaxCut” on a quantum computer. 

For 24 hours, the Blocheads worked towards a solution, guided by a three-step framework. First, they encoded the problem’s information into a quantum representation. Second, they created an algorithm to find the solution within that representation. And finally, they translated the quantum algorithm’s solution into a relevant answer for the problem. 

The team members worked into the early morning hours at Kirkland House, but they weren’t getting the results they’d hoped for. Then, just two hours shy of the deadline, their code’s performance improved dramatically. They pushed through in order to finalize everything and submitted their solution in the nick of time. It was an “adrenaline shock,” said Rassou. After the submission, there was one final task: a presentation where the Blocheads were assessed on their algorithm’s performance – how well their solution ran on an actual quantum computer – and their ability to communicate their work effectively. 

Through their combined efforts, the Blocheads earned 3rd place in the IonQ challenge. This qualified them for the championship round of the first International Quantum Circuit (IQC25), part of a series of events in celebration of 2025 as the International Year of Quantum Science and Technology.

In early October, with the support of Tarr-Coyne Professor of Applied Physics and Electrical Engineering Evelyn Hu and the Harvard Quantum Initiative (HQI), the five undergraduates found themselves on a plane bound for IQC25, hosted by the University of South Carolina. 

At the championship round, called QuantathonV2, the Blocheads were assigned another IonQ challenge. This time, the challenge tasked teams with creating an algorithm that could solve a block puzzle called “Instant Insanity” on a quantum computer. As explained on the GitHub repository for the challenge, Instant Insanity is a puzzle where players are given a set of four cubes. Each face of a cube is painted one of four colors, and the objective is to arrange the cubes in a stack such that each side of the stack contains all four distinct hues.

The blocks’ playful colors belie the puzzle’s sophistication; according to Rassou, there are a “factorial number of arrangements” for the four cubes. Adding another layer of complexity to the mix: not even the judges knew the answer to the hackathon challenge. Rather than giving teams “toy problems,” noted Waldorf, sponsoring companies said, “‘here's a problem that we were working on pretty recently at the office.’” 

Following the three-step framework they developed at iQuHACK the Blocheads tried several approaches. Some worked better than others. When team members hit roadblocks, they asked themselves, “do we continue to try to push even further with that solution, or do we go back to the drawing board?” recounted Rassou. “Communication was a key throughout the team,” he said. “I think if everyone just was isolated and working by themselves, we wouldn't have got anything done.” 

For the presentation, the Blocheads showcased all their solutions. They discussed their “official” solution. But they also discussed the solutions they hadn’t fully finished. “I felt like in the presentation we really showed the judges mostly everything that we had worked on,” said Mackay. This gave everyone “quite the rewarding feeling,” he added. The Harvard Blocheads’ rewarding feeling doubled when they learned they came in first for their challenge.

But working on the challenge wasn’t the only exciting part of the weekend. The hackathon hosted 100 students from 37 global universities. As a result, connections abounded. “It ended up being…a really nice way to meet other people in quantum computing,” said Gupta of the hackathon. In fact, at iQuHACK earlier that year, Waldorf struck up a conversation with a researcher from the quantum computing company QuEra. The researcher was looking for someone to help him create animations about quantum computing. “I guess I just happened to fit that bill,” said Waldorf. This interaction begot a summer internship at QuEra, where Waldorf created an animation software to visualize quantum circuits and qubit operations.

When asked about advice for students who were considering joining a quantum hackathon, the Blocheads were quick to respond.

“Just do it,” said Sasirekha.

“Say yes and deal with the consequences later,” added Waldorf. “You think that you don't have the time. Just do it…You won't regret these opportunities.”

For the inexperienced quantum scientist, Mackay provided the following: “no matter how little [you] know, there's always a way to…use that in some way to- to help with the solution.” He continued, saying, “you also learn much more than you would expect during the actual hackathon, so don't let it be a reason to not go.”

Sasirekha jumped in, pointing out that quantum hackathons often host beginner workshops before or during the event itself. So even if you have no background in the field, “you have no other reason to say no.”

Rassou, who has never taken a physics class at Harvard, agreed with his teammates. “I really encourage anyone–you don't even have to have any experience. You don't even need to know, like, what really is a qubit or a quantum computer,” he said. “If you're interested in the frontier of science and the potential impact of that, I think it's definitely worth a look.”

With a smile, Gupta added, “you get to solve open problems with cutting edge technology. What's not to like?”