Department of Computer Science AGH and IBM Software Laboratory in Krakow invite to Krakow Quantum Informatics Seminar (KQIS)
Objectives:
• understand and discuss current problems in quantum informatics,
• discuss new quantum computing technologies,
• exchange ideas and research results,
• integrate information across different research teams,
• build a community around quantum informatics.
Venue: via Internet, Webex https://ibm.webex.com/meet/tomasz.stopa
Program:
Tuesday, 3rd of November, 2020, 9:30-11:00
Filip Maciejewski - Center for Theoretical Physics, Polish Academy of Sciences Al. Lotników 32/46, 02-688 Warszawa, Poland
Topic: Mitigation of measurement noise on quantum devices
PresentationAbstract:
Measurement (readout) noise has been demonstrated to be one of the dominant sources of errors in currently available quantum devices based on superconducting qubits. In this talk, I will discuss a few contributions which aim to mitigate this problem. I will start by describing how to efficiently model and characterize imperfect quantum measurements. Then I will describe a method to reduce the effects of those imperfections. The procedure is based on the characterization of the noise - data obtained in such characterization can be later used to suitably post-process results of further experiments, making them less noisy. In particular, I will demonstrate that our procedure is suitable to perform error-mitigation on problems that require simultaneous estimation of multiple marginal probability distributions (such as Quantum Approximate Optimization Algorithm). Finally, I will present the results of successful error-mitigation for experiments on 15 qubits on IBM’s quantum device. During the presentation, I will also provide a statistical analysis of the accuracy of the method. The concepts conveyed in this talk will be a mixture of ideas from work [1], and the on-going project in collaboration with M. Oszmaniec, F. Baccari, and Z. Zimboras.
References:
[1] F. B. Maciejewski, Z. Zimborás, and M. Oszmaniec, “Mitigation of readout noise in near-term quantum devices by classical post-processing based on detector tomography”, Quantum 4, 257 (2020).