Work

Boosting projective methods for quantum process and detector tomography

Year: 2025

Type: article

Abstract: We introduce two methods for quantum process and detector tomography. In the quantum process tomography method, we develop an analytical procedure for projecting the linear inversion estimation of a quantum channel onto the set of completely positive trace-preserving matrices. By integrating this method with alternate projection techniques, we achieve a three-order-of-magnitude improvement in approximating the closest quantum channel to an arbitrary Hermitian matrix compared to existing methods without compromising computational efficiency. Our second method extends this approach to quantum detector tomography, demonstrating superior efficiency compared to current techniques. Through numerical simulations, we evaluate our protocols across channels of up to four qubits in quantum process tomography and systems of up to six qubits in quantum detector tomography, showcasing superior precision and efficiency.

Source: Physical Review Research

DOI: 10.1103/physrevresearch.7.013208

Authors: Júlia Barberà-Rodríguez, Leonardo Zambrano, Antonio Acín, Donato Farina

Institutions: Institute of Photonic Sciences, Institució Catalana de Recerca i Estudis Avançats, University of Naples Federico II

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,625