Scholarlink

<p>We theoretically investigate the generation of nonclassical features, namely two-mode squeezing, sub-Poissonian photon statistics, and bipartite entanglement in the nondegenerate frequency up-conversion (NFUC) process using a&#xa0;first-order interaction Hamiltonian under the short-time approximation. First-order photon statistics in the pump modes remain Poissonian under coherent excitation, reflecting the inability of linear interactions to mediate the simultaneous multi-photon processes required for up-conversion. In contrast, higher-order effects reveal pronounced nonclassical features. Both first- and second-order squeezing show a&#xa0;strong dependence on coherent field amplitudes, interaction strength, and relative phase. Asymmetric input configurations, especially those with enhanced signal-mode intensity, notably deepen squeezing and boost nonclassicality. Second-order squeezing proves more sensitive to phase and amplitude imbalances than first-order, serving as a&#xa0;precise indicator of higher-order quantum correlations. Entanglement is analysed using the Duan et&#xa0;al. inseparability criterion and the Hillery-Zubairy (HZ) criteria. The Duan criterion yields a&#xa0;value at the separability threshold under coherent excitation, indicating the presence of entanglement. HZ‑1 and HZ‑2 reliably detect bipartite entanglement under suitable conditions. HZ‑2 exhibits higher sensitivity at increased field strengths. Entanglement is confined to the pump modes, which are directly and symmetrically involved in the nonlinear interaction. The signal mode, as a&#xa0;collective outcome, does not display entanglement with either pump individually, highlighting the collective nature of quantum correlations in NFUC. These findings emphasise the importance of field asymmetry and higher-order dynamics in engineering entanglements, confirming the NFUC as a&#xa0;promising platform for tunable, nonclassical light generation in quantum optics and integrated photonics.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Two-mode squeezing and entanglement in nondegenerate frequency up-conversion under first-order interaction hamiltonian

  • 期刊论文

  • 发表日期：

    2026年4月14日

查看全文
  • Sourish Sarkar,
  • Dilip Kumar Giri

摘要

We theoretically investigate the generation of nonclassical features, namely two-mode squeezing, sub-Poissonian photon statistics, and bipartite entanglement in the nondegenerate frequency up-conversion (NFUC) process using a first-order interaction Hamiltonian under the short-time approximation. First-order photon statistics in the pump modes remain Poissonian under coherent excitation, reflecting the inability of linear interactions to mediate the simultaneous multi-photon processes required for up-conversion. In contrast, higher-order effects reveal pronounced nonclassical features. Both first- and second-order squeezing show a strong dependence on coherent field amplitudes, interaction strength, and relative phase. Asymmetric input configurations, especially those with enhanced signal-mode intensity, notably deepen squeezing and boost nonclassicality. Second-order squeezing proves more sensitive to phase and amplitude imbalances than first-order, serving as a precise indicator of higher-order quantum correlations. Entanglement is analysed using the Duan et al. inseparability criterion and the Hillery-Zubairy (HZ) criteria. The Duan criterion yields a value at the separability threshold under coherent excitation, indicating the presence of entanglement. HZ‑1 and HZ‑2 reliably detect bipartite entanglement under suitable conditions. HZ‑2 exhibits higher sensitivity at increased field strengths. Entanglement is confined to the pump modes, which are directly and symmetrically involved in the nonlinear interaction. The signal mode, as a collective outcome, does not display entanglement with either pump individually, highlighting the collective nature of quantum correlations in NFUC. These findings emphasise the importance of field asymmetry and higher-order dynamics in engineering entanglements, confirming the NFUC as a promising platform for tunable, nonclassical light generation in quantum optics and integrated photonics.