Abstract
This work investigates the emergence of Non-classical Features in a pump-free hybrid atom-optomechanical system, addressing key limitations of conventional platforms that rely on strong coherent driving and are highly vulnerable to thermal decoherence. We propose a novel architecture in which a squeezed vacuum reservoir acts as a pre-correlated quantum environment, enabling the deterministic generation and stabilization of nonclassical correlations without the need for an external laser pump. By exploiting reservoir-engineered interactions, the system supports robust quadrature squeezing and multipartite entanglement across a wide range of operational parameters. Our analysis demonstrates that the hybrid system achieves significant squeezing levels approaching 90%, while simultaneously satisfying the DGCZ inseparability criterion, confirming the presence of strong continuous-variable entanglement. Importantly, these nonclassical signatures remain resilient under extreme thermal conditions, withstanding thermal occupancies as high as (nth = 1500), which substantially exceeds the tolerance of traditional laser-driven optomechanical systems. The underlying mechanism is attributed to passive correlation injection from the engineered reservoir, which effectively suppresses thermal noise and enhances quantum coherence even in weak-coupling and low-power regimes. This eliminates the need for active pumping, thereby reducing energy consumption and experimental complexity. Furthermore, the hybrid atom-optomechanical configuration introduces additional tunability through atomic gain and population inversion, thereby allowing flexible control over system dynamics and correlation properties. Overall, the proposed scheme establishes a scalable and energy-efficient pathway toward realizing robust quantum correlations in realistic noisy environments. It opens new prospects for cryogen-free quantum technologies, including quantum-enhanced sensing, precision metrology, and long-distance entanglement distribution.