In the News
September 17, 2020
A new work has been posted on the arXiv entitled 'Extended Flag Gadgets for Low-Overhead Circuit Verification.' In this work we propose an extension to the flag qubit framework which can be applied in a more general setting. Our gadgets can detect faults on generic unitaries, and are low overhead [...]
August 20, 2020
Our new preprint on coupling molecular and atomic ion qubits can be found at arXiv:2008.09201 .This work is in collaboration with the Eric Hudson and Wes Campbell groups at UCLA and Michael Heaven at Emory University. In this article we discuss a novel laser-free method of using an atomic ion for [...]
April 10, 2020
New paper published in the International Symposium on Computer Architecture (ISCA2020)!
March 13, 2020
Leakage is a particularly damaging error that occurs when a qubit leaves the defined computational subspace.
March 12, 2020
Our detailed study of photon-mediated charge exchange between cold Potassium atoms and calcium ions is published in the journal Physical Chemistry Chemical Physics.
January 13, 2020
Brown lab at QIP2020 in Shenzhen. Posters about quantum error correction by Natalie, Shilin, Dripto, and Muyuan. Talks about quantum error correction by Mike and Ken.
November 13, 2019
Brown lab attended the Southeastern Section of the American Physical Society (SESAPS) in Wilmington.
October 18, 2019
Swarnadeep Majumder attended the Assessing Performance of Quantum Computers (APQC) workshop in Estes Park, CO and presented a poster on Real Tiime Calibration Using Spectator Qubits.
October 17, 2019
Quantum information is delicate. To preserve it, we must constantly interact with our system in order to remove errors.
August 5, 2019
Cold molecular ions are good candidates for precision measurements such as the time variation of proton to electron mass ratio.
August 4, 2019
Brown lab attended the 5th International Conference on Quantum Error Correction in London.
July 16, 2019
Quantum computers promise to be a technological revolution, but they will only be possible if the error rate of quantum bits (qubits) is kept under a manageable level. Many techniques have been developed to control, mitigate, and correct quantum errors, and the most appropriate choice depends [...]
June 4, 2019
Ken Brown and Swarnadeep Majumder attend TQC 2019 conference + NISQ workshop. Ken presents an invited talk on Error Reduction, Fault Tolerance, and Scalability at TQC. Swarnadeep presents a poster on real-time calibration with spectator qubits at the NISQ workshop.
May 14, 2019
Mixed species surface code layout. Hyperfine (171Yb+) ions are defined as ancilla qubits (white) and Zeeman (174Yb+) ions are defined as data qubits (black). The green (blue) diamond represents an X (Z) stabilizer measurement. Leakage errors are exceptionally damaging errors that occur when a [...]
March 12, 2019
The distance-3 and distance-5 rotated subsystem surface codes. Although the weight-6 rectangular stabilizers are larger than the weight-4 stabilizer of the surface code, they can be measured in pairs of triangular gauge operators. This locality limits correlated errors due to leakage, resulting [...]