Year: 2025
Type: article
Abstract: Designs, structures connected to averaging with respect to a given measure using finite sets of points, have proven themselves to be invaluable tools across the field of quantum information, finding their uses in state and process tomography, key distribution, and others. In this work, we introduce a concept of pushforward designs that allows us to obtain new structures from already existing ones by mapping them between the spaces, with specific examples including simplex designs and mixed state designs from complex projective designs. Based on the general concept, we put forward a structure called channel $[t,k]$-design, allowing for averaging over space of quantum channels for systems in contact with an environment of dimension $k$. Based on this notion, we introduce the concept of effective environment dimensionality ${k}^{*}$, which we estimate for the IBM Kyoto quantum computer to be below 2.2 for times up to $350\phantom{\rule{4pt}{0ex}}\textmu{}\text{s}$.
Source: Physical Review A
Authors: Jakub Czartowski, Karol Życzkowski
Institution: Jagiellonian University
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4408905251