arXiv subjects

S. G. N. Engo

Publications and source records attributed to S. G. N. Engo.

3 recordsLinked to original sources

arXiv2025

Quantum phase synchronisation enhanced via Coulomb interaction in an optomechanical system

In this work, we investigate the dynamics of quantum synchronization in a four-mode optomechanical system, focusing on the influence of the Coulomb interaction between two mechanical resonators. We analyze the effect of the Coulomb coupling on three distinct synchronization regimes, i.e., complete quantum synchronization, $ϕ$-synchronization, and quantum phase synchronization. Our results show that while the Coulomb interaction plays a pivotal role in significantly enhancing quantum phase synchronization by facilitating energy exchange and phase coherence, it has little impact on complete and $ϕ$-synchronization. This indicates that amplitude and frequency locking are primarily determined by the optical driving, whereas phase alignment depends critically on inter-resonator coupling. We also demonstrate that the oscillations of the two optical cavities, which are indirectly coupled via the mechanical resonators, can become aligned over time, resulting in classical synchronization. These findings provide a robust mechanism for controlling collective quantum dynamics and offer a foundation for applications in quantum communication, precision sensing, and the development of synchronized quantum networks.

quant-ph↗

arXiv2025

Nonreciprocal transmission in hybrid atomic ensemble-optomechanical systems

We investigate perfect optical nonreciprocal transmission in a hybrid optomechanical system that incorporates an atomic ensemble. By introducing complex coupling strengths between the atomic ensemble and a mechanical oscillator, nonreciprocity is induced through interference between distinct optical pathways. The nonreciprocal transmission is governed by the real and imaginary components of the coupling constants, along with the relative phase differences between the optomechanical couplings. Our analysis reveals that, with precise tuning of system parameters, such as coupling strengths, detuning, and phase differences, perfect nonreciprocity can be achieved. We derive the conditions necessary for optimal nonreciprocal transmission and demonstrate its dependence on the complex nature of the coupling. These findings offer valuable insights for the design of nonreciprocal optical devices, including isolators and circulators, with potential applications in quantum communication, signal processing, and photonics.

quant-ph↗

arXiv2024

Quantum correlations enhanced in hybrid optomechanical system via phase tuning

This work presents a theoretical framework for enhancing quantum correlations in a hybrid double-cavity optomechanical system that hosts an atomic ensemble. We investigate the role of the coupling phase $ϕ$ between cavity 1 and the atomic ensemble in optimizing quantum correlations, i.e., bipartite/tripartite quantum entanglement and quantum discord. By employing metrics such as logarithmic negativity for bipartite entanglement and minimum residual contangle for genuine tripartite entanglement, we demonstrate that tuning the phase $ϕ$ is essential for maximizing photon-phonon entanglement. Specifically, we find that optimal entanglement occurs at $ϕ=nπ$, with distinct conditions for odd and even integers $n$. Our results also indicate that the quantum entanglement achieved in this system is robust against thermal fluctuations, making it a promising candidate for applications in quantum information processing and quantum computing. Furthermore, this research highlights the significance of phase tuning in controlling quantum correlations, paving the way for advancements in quantum technologies.

quant-ph↗