Quantum squeezing effects in coupled van der Pol oscillators

Achieving synchronized quantum states within the quantum realm is a significant goal. This regime is characterized by restricted excitation occurrences and a highly nonclassical stable state of the self-oscillating system. However, many existing approaches to observe synchronization in this quantum realm face a major challenge: the influence of noise tends to overshadow the synchronization phenomenon. In coupled van der Pol oscillators, synchronization occurs when a system of two or more oscillators interacts. Our investigation demonstrates that introducing the squeezing Hamiltonian in two coupled van der Pol oscillators enhances nonclassical effects, increases quantum correlations, and improves the robustness of synchronization dynamics. This was evidenced through the analysis of the Wigner function and power spectrum, showing significant improvements compared to systems without squeezing.