ELFT HÍRADÓ

[Andras Palyi <palyi AT mail.bme.hu>]

Dear Colleagues, 

Next Monday the BME Exotic Quantum Phases seminar series continues with this 
talk:
 
Speaker: Zoltan Zimboras (Wigner/BME)
Title: Mitigation of readout errors in near-term quantum devices by classical 
post-processing based on detector tomography
Abstract: please find below 
Time: Oct 5 Monday, 14:15
Location: online in Teams, join with this link:

https://teams.microsoft.com/l/meetup-join/19%3a28ae69eb950d4367acfc0ead8e90b8e6%40thread.tacv2/1601656712032?context=%7b%22Tid%22%3a%226a3548ab-7570-4271-91a8-58da00697029%22%2c%22Oid%22%3a%22f8b27e90-dbca-4bb5-813c-d6415577ec35%22%7d
 
<https://teams.microsoft.com/l/meetup-join/19%3a28ae69eb950d4367acfc0ead8e90b8e6%40thread.tacv2/1601656712032?context=%7b%22Tid%22%3a%226a3548ab-7570-4271-91a8-58da00697029%22%2c%22Oid%22%3a%22f8b27e90-dbca-4bb5-813c-d6415577ec35%22%7d>
 
Best regards,
Andras Palyi
 
= = = 
 
Abstract: "We propose a scheme to reduce readout errors in experiments on 
quantum systems with finite number of measurement outcomes. Our method relies 
on performing classical post-processing which is preceded by Quantum Detector 
Tomography, i.e., the reconstruction of a Positive-Operator Valued Measure 
(POVM) describing the given quantum measurement device. If the measurement 
device is affected only by an invertible classical noise, it is possible to 
correct the outcome statistics of future experiments performed on the same 
device. To support the practical applicability of this scheme for near-term 
quantum devices, we characterize measurements implemented in IBM's and 
Rigetti's quantum processors. We find that for these devices, based on 
superconducting  transmon qubits, classical noise is indeed the dominant 
source of readout errors. Moreover, we analyze the influence of the presence 
of coherent errors and finite statistics on the performance of our 
error-mitigation procedure. Applying our scheme on the IBM's 5-qubit device, 
we observe a significant improvement of the results of a number tasks 
including Quantum State Tomography, Quantum Process Tomography, the 
implementation of non-projective measurements, and certain quantum 
algorithms, such as Grover's search, the Bernstein-Vazirani algorithm and the 
quantum approximate optimization algorithm.

F. B. Maciejewski, Z. Zimborás, M. Oszmaniec, Quantum 4, 257 (2020)"