Correlated errors in quantum computers emphasize need for design changes

rtist rendition of a 4-qubit chip with a dotted-line-like cosmic ray hitting it from out of the image frame, lighting up two neighboring qubits "red" to indicate they are affected by the cosmic ray's energy

Quantum computers could outperform classical computers at many tasks, but only if the errors that are an inevitable part of computational tasks are isolated rather than widespread events.

Now, researchers at the University of Wisconsin–Madison have found evidence that errors are correlated across an entire superconducting quantum computing chip — highlighting a problem that must be acknowledged and addressed in the quest for fault-tolerant quantum computers.

The researchers report their findings in a study published June 16 in the journal Nature, Importantly, their work also points to mitigation strategies.

“I think people have been approaching the problem of error correction in an overly optimistic way, blindly making the assumption that errors are not correlated,” says UW–Madison physics Professor Robert McDermott, member of the Wisconsin Quantum Institute and senior author of the study. “Our experiments show absolutely that errors are correlated, but as we identify problems and develop a deep physical understanding, we’re going to find ways to work around them.”

Read the full story at https://news.wisc.edu/correlated-errors-in-quantum-computers-emphasize-need-for-design-changes/

Welcome, incoming MSPQC students!

The UW–Madison Physics Department and the Wisconsin Quantum Institute are pleased to welcome 18 students to the M.S. in Physics – Quantum Computing program. These students make up the third cohort to begin the program and are the largest entering class to date.  

“We are really pleased and proud that the MSPQC program continues to grow and prosper in its third year,” says Bob Joynt, MSPQC Program Director, professor of physics, and WQI member. “We look forward to providing a great experience for the class of 2021. A particular focus this year will be the formation of collaborative teams that will push forward research in quantum computing.” 

 Of note, three women are in the entering class, marking the first time that women have enrolled in MSPQC. Other facts and figures about this year’s cohort include: 

  • 11 students are coming directly from completing their Bachelors 
  • Three students have Master’s degrees 
  • Six students have at least four years of professional experience, and four of those students have over 10 years professional experience 
  • 15 are international students, and seven of those students have attended U.S. institutions for previous studies 
  • The students’ academic backgrounds include physics, astronomy, engineering, and business administration.  

The department is following University guidelines and is planning for students to join us in Madison this fall, with in-person instruction. Over the summer, students can attend optional virtual orientation sessions to prepare for the program.  

“The pandemic imposed restrictions on our admissions and recruitment activities which forced us to work virtually, but I believe these barriers made our programming more accessible and led to the most diverse and determined incoming cohort of MSPQC students to date,” says Jackson Kennedy, MSPQC coordinator. “Although I have been able to meet our incredibly talented students virtually, I cannot wait to greet them in-person this Fall as we celebrate a long-awaited return to campus.” 

In addition to Joynt, the department thanks the other faculty who serve on the MSPQC admissions committee — Alex Levchenko, Robert McDermott, Maxim Vavilov and Deniz Yavuz — for application review. We also thank Michelle Holland and Jackson Kennedy for organizing recruiting efforts.  

 The MSPQC program welcomed its first students in Fall 2019 – the first-ever class of students in the U.S. to enroll in a quantum computing M.S. degree program. The accelerated program was born out of a recognized need to rapidly train students for the quantum computing workforce and is designed to be completed in 12 months. It provides students with a thorough grounding in the new discipline of quantum information and quantum computing.  

list of names, UG institutions, and majors: Brooke Becker UW–Madison Computer Engineering Soyeon Choi Vanderbilt University Physics, Computer Science Manish Chowdhary Indian Institute of Technology Dhanbad Computer Application Hua Feng Dalian University of Technology Atomic and Molecular Physics Jacob Frederick University of Washington Computer Engineering Amol Gupta Delhi Technological University Computer Engineering Yucheng He Zhengzhou University Automation Xunyao Luo Lafayette College Physics and Neuroscience Arjun Puppala Indian Institute of Technology Roorkee Power Systems Engineering Evan Ritchie University of St Thomas - Minnesota Physics & Math Mubinjon Satymov New York City College of Technology - CUNY Applied Computational Physics Yen-An Shih National Cheng Kung University Computer Science Qianxu Wang University of Michigan Physics Jiaxi Xu UC-Berkeley Physics Anirudh Yadav Indian Institute of Technology Dhanbad Computer Science Yukun Yang Nanjing University Astronomy Jin Zhang UW–Madison Physics & Philosophy Lin Zhao UW–Madison Computer Science and Physics
The 18 students of the incoming 2021 class