Skip to navigation Skip to content
Careers | Phone Book | A - Z Index

Berkeley Lab Researchers Honored with Best Paper Award at QCE21

October 25, 2021

Two researchers from Berkeley Lab’s Applied Mathematics & Computational Research Division (AMCRD) are co-authors on a paper selected as Best Paper in the Quantum Computing and Systems Track at the 2021 IEEE International Conference on Quantum Computing and Engineering (QCE21), held virtually October 17-22.

Ed Younis and Costin Iancu are both with the Computer Languages and Systems Software group within AMCRD. Their co-authors are Koushik Sen and Katherine Yelick, both with the University of California, Berkeley.


Ed Younis (left), Costin Iancu (right)

The paper outlines QFAST (Quantum Fast Approximate Synthesis Tool), designed to improve scalability by trading off search computational complexity with numerical optimization complexity. It implements a bottom-up synthesis approach whose main contribution comes from encoding and using generic computational building blocks encoded with Pauli operators. It also features a three-stage, topology-aware hierarchical algorithm, which can be composed with other third party code generators for portability. As a result, QFAST has been shown to scale up to seven qubits, producing circuits shorter by up to two orders of magnitude than other state-of-the-art techniques.

“Our goal is to build a scalable circuit optimizer able to reduce the resource consumption (gates) of quantum circuits, when compared to more traditional peephole based quantum compilers,” said Younis, who is lead author on the QCE21 paper. “Besides being in itself a very competitive optimizer for small circuits, QFAST is a very important building block in our BQSKit (Berkeley Quantum Synthesis Toolkit) infrastructure, which enables scalability up to hundreds of qubits. Inside BQSKit, QFAST provides an orthogonal but synergistic approach to our previous QSearch algorithm, which won a Best Paper award at QCE20. We encourage folks to keep an eye on BQSKit; we have more very interesting breakthroughs to announce soon.”

This work was supported by the U.S. Department of Energy through the Office of Advanced Scientific Computing Research Quantum Algorithms Team and Accelerated Research in Quantum Computing programs.

About Berkeley Lab

Founded in 1931 on the belief that the biggest scientific challenges are best addressed by teams, Lawrence Berkeley National Laboratory and its scientists have been recognized with 16 Nobel Prizes. Today, Berkeley Lab researchers develop sustainable energy and environmental solutions, create useful new materials, advance the frontiers of computing, and probe the mysteries of life, matter, and the universe. Scientists from around the world rely on the Lab’s facilities for their own discovery science. Berkeley Lab is a multiprogram national laboratory, managed by the University of California for the U.S. Department of Energy’s Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit