Department of Computer Science AGH and IBM Software Laboratory in Krakow invite to Krakow Quantum Informatics Seminar (KQIS)
• 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
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
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 , and the on-going project in collaboration with M. Oszmaniec, F. Baccari, and Z. Zimboras.
 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).