### Quantum programming for computers and humans

Zhiding Liang, PhD student, Department of Computer Science and Engineering

*and*one at the same time — a phenomenon called “superposition.”Superposition enables quantum computers to wield immense computational power since the amount of information a system can process grows exponentially with each additional qubit.However, quantum computers have limitations. In terms of hardware, qubits are incredibly fragile devices. To maintain a state of superposition, qubits require particular environmental conditions (temperature, noise, etc.). If such conditions are not maintained, qubits could experience “decoherence,” or losing their power of superposition, and, in effect, devolving into classical binary bits.Liang focuses on solving problems on the software side of things. His research looks at ways to optimize quantum computer architecture to improve the performance of algorithms. The difficulty of maintaining superposition and avoiding decoherence often limits the time in which quantum computation is possible. So, decreasing the latency of these systems (the time it takes to send data) is important for making quantum computers usable.When he isn’t programming quantum computers, Liang works on a different kind of programming: educational lectures about quantum computing for fellow students.As an electrical engineer, Liang came to quantum computing without background knowledge in physics, which is necessary even for software-focused researchers like himself.Liang said that his first semester as a PhD student involved extensive studies outside of class to get up to speed on fundamental physics concepts. This was frustrating due to the lack of resources online and even from other universities.Liang was inspired to create the Quantum Computer System Lecture Series to make the transition to quantum computing easier for students like himself who do not have a physics background.“I think there’s not enough open source resources online,” Liang said. “I hope to offer a platform to let students who are interested in quantum computing have a pathway to get in touch with this area.”The lecture series has featured 33 talks from quantum computing students and researchers from around the world. Topics range from introductions to basic quantum concepts to state-of-the art research outcomes.Liang hopes that his lecture series will spark interest in quantum computing at Notre Dame. He recognizes that this field can be intimidating due to the high knowledge bar and uncertainty about when this technology will arrive. But he is optimistic about quantum computers and the opportunities for Notre Dame and its students.“I want to contribute to building a quantum computing community at Notre Dame,” Liang said. “Quantum computing is still a really young area. There’s lots of things you can do … there’s a lot of opportunities.”

### Getting “quantum ready” in Silicon Valley

Mariya Vyushkova, Quantum Computing Research Specialist at the Notre Dame Center for Research Computing, Visiting Scientist at IBM Research

### Building a center for quantum innovation

Laszlo Forro, Aurora and Thomas Marquez Professor of Physics of Complex Quantum Matter, Director of Stavropoulos Center for Complex Quantum Matter