Enhancing non-classicality by superposing two induced states from coherent states
Document Type
Article
Publication Date
11-1-2022
Abstract
Non-classical states induced from coherent states (CS) vertical bar alpha > via photon addition operations have useful non-classical properties that improve performances in quantum information processing. Two examples of such induced states are displaced n-photon Fock states (n-DPFS) and n-photon added coherent states (n-PACS). Quantum superposition of n-DPFS and n-PACS results in a new state, superposed-n-DPFS-n-PACS (n-SDP) which has better non-classicality. Specifically, n-SDP exhibits stronger quadrature squeezing, anti-bunching and sub-Poisson compared to n-DPFS and n-PACS. The general enhancements of n-SDP non-classicality over n-DPFS and n-PACS are due to quantum interference effects. For example, for average photon-number vertical bar alpha vertical bar(2) <= 1 and n = 1, 1-SDP has quadrature squeezing; however, 1-DPFS and 1-PACS did not. At the limit of vertical bar alpha vertical bar(2) >> 1, n-SDP exhibits better quadrature squeezing, anti-bunching and sub-Poisson than n-DPFS and n-PACS. Furthermore, using input states of n-SDP and CS in a Mach-Zehnder interferometer enhance phase sensitivity beyond standard quantum limit. Finally, a possible generation of n-SDP by using a seeded optical parametric amplifier with conditional measurement is proposed.
Keywords
Non-classical state, Displaced Fock states, Photon added coherent states, Quantum superposition, Optical interferometry
Divisions
PHYSICS
Funders
Ministry of Education, Malaysia [FRGS/1/2020/STG07/UKM/02/2]
Publication Title
INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS
Volume
61
Issue
11
Publisher
SPRINGER/PLENUM PUBLISHERS
Publisher Location
233 SPRING ST, NEW YORK, NY 10013 USA