Quantum Science and Engineering Seminar - Daniel Lidar

Dr. Lidar is the Viterbi Professor of Engineering at the University of Southern California and Co‑Founder and CSO of Quantum Elements. His seminar, “Demonstrations of Quantum Speedup and Deterministic Benchmarking,” will present recent experimental demonstrations of provable quantum speedup and introduce deterministic benchmarking methods for characterizing coherent errors in quantum systems.

This talk will cover two separate topics. In the first half, I will report on two demonstrations of provable algorithmic quantum speedups. The first demonstration is based on the single-shot Bernstein-Vazirani algorithm, which efficiently solves the problem of identifying a hidden bitstring that changes after every oracle query. We implemented this algorithm utilizing two different 27-qubit IBM QPUs. The second demonstration, using 127-qubit IBM QPUs, is based on the restricted Hamming weight Simon’s problem, which likewise efficiently solves the problem of identifying a hidden bitstring encoded into an unknown periodic function. The speedups are observed when the computation is protected by dynamical decoupling, but not without it. In contrast with quantum supremacy demonstrations, the quantum speedup reported here does not rely on complexity-theoretic conjectures. In the second half, I will present our recent work on Deterministic Benchmarking, an efficient noise characterization method that captures coherent errors beyond standard stochastic error models. I will discuss its application to characterizing the noise afflicting transmon qubits, and demonstrate its advantages over randomized benchmarking.

References: PRL 130, 210602 (2023); PRX 15, 021082 (2025); Chem. Rev. 125, 5745 (2025)

Daniel Lidar is the holder of the Viterbi Professorship of Engineering at the University of Southern California and researches quantum information processing. He holds joint appointments in the departments of Electrical & Computer Engineering, Chemistry, and Physics & Astronomy. He is the co-founder and CSO of Quantum Elements, Inc.

For more information:

Liang Jiang | liangjiang@uchicago.edu
Chicago Quantum Institute | qi@uchicago.edu