In recent years, there has been a spurring research interest growing on photonics integrated circuits as the way to scale up quantum communications. In particular, building a reliable integrated source of entangled photons is one of the main challenges remaining for commercial exploitation in quantum sensing and metrology. Therefore, advances in design of integrated sources of entangled photons is a necessary and crucial task to be performed for miniaturization and cost-effectiveness. Microring resonators are one of the most promising candidates to generate entangled photons via nonlinear interactions, especially Spontaneous Four-Wave Mixing (SFWM). But fabrication limitations in reproducibility of high-quality resonators mandate the use of active devices. Here we present the results of preparing the excitation pulse with different spectral, intensity and dispersion parameters to optimize the quantum efficiency in passive devices after fabrication. Different numerical methods such as Finite Difference Time Domain (FDTD) and Split-Step Fourier Method (SSFM) are used to reproduce the nonlinear propagation, interplay with dispersion and losses. Exploiting the degree of freedom of the excitation pulse can bring more energy efficient and passive devices as quantum entangled pair sources in an integrated chip. Considerations on different degrees of entanglement are also discussed for applications in quantum sensing and quantum metrology.
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