2020/04/30 by Chandan Kumar, Ritabrata Sengupta, Arvind +1
Computer Science · Physics and Astronomy · #Detector #Gaussian #Optics #Photon #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum channel #Quantum computer #Quantum entanglement #Quantum key distribution #Quantum mechanics #Quantum state #Quantum tomography #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physreva.102.012616
published as Phys. Rev. A 102, 012616 (2020) · 11 Pages 6 figures Revtex
openalex publication_date 2020/07/16 · openalex created_date 2020/07/23 · arxiv created 2020/07/24 · arxiv updated 2020/07/27 · openalex updated_date 2026/08/05
We present optimal schemes, based on photon-number measurements, for Gaussian state tomography and for Gaussian process tomography. An n-mode Gaussian state is completely specified by 2n2+3n parameters. Our scheme requires exactly 2n2+3n distinct photon-number measurements to tomograph the state and is therefore optimal. Furthermore, we describe an optimal scheme to characterize Gaussian processes by using coherent-state probes and photon-number measurements. With much recent progress in photon-number-measurement experimental techniques, we hope that our scheme will be useful in various quantum information processing protocols including entanglement detection, quantum computation, quantum key distribution, and quantum teleportation. This work builds upon the work of Parthasarathy and Sengupta [Infin. Dimens. Anal. Quantum Probab. Relat. Top. 18, 1550023 (2015)].