Journal of Modern Optics

Multipartite entanglement in nondegenerate triple-photon down-conversion

Sourish Sarkar, Dilip Kumar Giri

Published Apr 23, 2026• 0 citations

Abstract

We present a theoretical study of nonclassical light generation in Nondegenerate Triple-Photon Down-Conversion (NTPDC), using a first-order interaction Hamiltonian within the short-time approximation. The analysis reveals quadrature squeezing and both bipartite and tripartite entanglement, indicating strong multimode quantum correlations. We show that increasing the coherent input amplitude and the nonlinear coupling enhances the degree of two-mode squeezing, while the squeezing depth is strongly controlled by the relative phase, enabling suppression of quantum noise. Bipartite entanglement is stronger and persists over a wider parameter range than tripartite entanglement, which occurs only under symmetric excitation and precise phase matching. The presence of bipartite entanglement is quantitatively verified using the Hillery-Zubairy (HZ) criteria (HZ-1 and HZ-2), with HZ-1 exhibiting higher sensitivity in high-coherence regimes. The results demonstrate that NTPDC is a promising scheme for generating scalable quantum resources for applications in quantum information and integrated photonics.

DOI: 10.1080/09500340.2026.2662654

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