Search

In this manuscript, we investigate the enhancement of the transfer of quantum correlations from squeezed light to movable mirrors within an optomechanical system. This enhancement was achieved via the injection of squeezed light in the cavities and via intracavity squeezed light. We quantify the entanglement between mechanical oscillators via logarithmic negativity. We demonstrate that entanglement is influenced by various factors, including the gain of the parametric amplifier, the squeezing parameter characterizing the squeezed light, the rate of the phonon tunneling process, the coupling strength of the photon hopping process and the bath temperature of the mechanical oscillators. We have shown that entanglement can be improved by a convenient choice of coupling strength in the case of the photon hopping process, as well as for specified values of the gain of the parametric amplifier. [ABSTRACT FROM AUTHOR]

In this work, the study focuses on an optomechanical system composed of two Fabry–Pérot cavities each pumped by a coherent laser source, and coupled by photon hopping process, phonon tunneling and by a squeezed light source. We theoretically investigate the impact of increasing the squeezing parameter of squeezed light on the sharing of quantum correlations between two mechanical modes and an optical mode, then between two optical modes and a mechanical mode using logarithmic negativity. Then, we study the effect of different couplings on the emergence and degree of tripartite entanglement by tripartite negativity. As a result, the entanglement shared in each considered three-mode block is monogamous and during the evolution the one-mode versus one-mode entanglement always remains less than one-mode versus two-mode entanglement. Moreover, the combined effect of different couplings can enhance tripartite entanglement in certain conditions as it can degrade it in other ones. Our results indicate that the proposal systems could provide an important platform for the study of macroscopic quantum phenomena. [ABSTRACT FROM AUTHOR]

Characterizing and quantifying quantum entanglement in states of open quantum systems are at the heart of quantum information theory. In this work, we study the mixedness and entanglement of a two-mode symmetrical Gaussian state evolving in a thermal Markovian environment. The considered state is that of two movable end-mirrors of two distant Fabry–Pérot cavities coupled via a two-mode squeezed light and driven by coherent lasers. We use the logarithmic negativity to consistently quantify the degree of entanglement between the two mechanical modes. The purity is employed as a witness of mixedness and characterize of entanglement in the two-mode mechanical bi-partition. By comparing the behavior of the logarithmic negativity with that of the purity under the effect of various parameters and based on the entanglement classification established in [G. Adesso, A. Serafini and F. Illuminati, Phys. Rev. Lett.92, 087901 (2004)], we found that the purity can be used as a characterize and measure of entanglement in the two-mode symmetrical state when the squeezing parameter is fixed. The effects of thermal noise, squeezing and optomechanical coupling are also discussed in detail. [ABSTRACT FROM AUTHOR]