Abstract

The paper proposes on-chip high-order parametric downconversion in monolayer Nb₃Cl₈ for programmable multiphoton entangled states. Using many-body GW-BSE and time-dependent BSE / Kadanoff-Baym simulations, it reports exceptionally large nonlinear susceptibilities up to seventh order in monolayer Nb₃Cl₈ and attributes the response to flat bands and strongly bound Frenkel excitons with ferroelectrically aligned out-of-plane dipoles. The work combines these ab initio results with integrated 1×N splitter architectures to derive n-photon generation rates and to propose GHZ, W, and cluster-state sources.

Abstract

The paper proposes on-chip high-order parametric downconversion in monolayer Nb₃Cl₈ for programmable multiphoton entangled states. Using many-body GW-BSE and time-dependent BSE / Kadanoff-Baym simulations, it reports exceptionally large nonlinear susceptibilities up to seventh order in monolayer Nb₃Cl₈ and attributes the response to flat bands and strongly bound Frenkel excitons with ferroelectrically aligned out-of-plane dipoles. The work combines these ab initio results with integrated 1×N splitter architectures to derive n-photon generation rates and to propose GHZ, W, and cluster-state sources.

Abstract

The paper proposes on-chip high-order parametric downconversion in monolayer Nb₃Cl₈ for programmable multiphoton entangled states. Using many-body GW-BSE and time-dependent BSE / Kadanoff-Baym simulations, it reports exceptionally large nonlinear susceptibilities up to seventh order in monolayer Nb₃Cl₈ and attributes the response to flat bands and strongly bound Frenkel excitons with ferroelectrically aligned out-of-plane dipoles. The work combines these ab initio results with integrated 1×N splitter architectures to derive n-photon generation rates and to propose GHZ, W, and cluster-state sources.

Abstract

The paper proposes on-chip high-order parametric downconversion in monolayer Nb₃Cl₈ for programmable multiphoton entangled states. Using many-body GW-BSE and time-dependent BSE / Kadanoff-Baym simulations, it reports exceptionally large nonlinear susceptibilities up to seventh order in monolayer Nb₃Cl₈ and attributes the response to flat bands and strongly bound Frenkel excitons with ferroelectrically aligned out-of-plane dipoles. The work combines these ab initio results with integrated 1×N splitter architectures to derive n-photon generation rates and to propose GHZ, W, and cluster-state sources.