Dissipative generation of significant amount of mechanical entanglement in a coupled optomechanical system

Abstract

We propose an approach for generating steady-state mechanical entanglement in a coupled optomechanical system. By applying four-tone driving lasers with weighted amplitudes and specific frequencies, we obtain an effective Hamiltonian that couples the delocalized Bogoliubov modes of the two mechanical oscillators to the cavity modes via beam-splitter-like interactions. When the mechanical decay rate is small, the Bogoliubov modes can be effectively cooled by the dissipative dynamics of the cavity modes, generating steady-state entanglement of the mechanical modes. The mechanical entanglement obtained in the stationary regime is strongly dependent on the values of the ratio of the effective optomechanical coupling strengths. Numerical simulation with the full linearized Hamiltonian shows that significant amount of mechanical entanglement can indeed be obtained by balancing the opposing effects of varying the ratio and by carefully avoiding the system parameters that may lead to amplified oscillations of the mechanical mean values detrimental to the entanglement generation.

Enhancement of steady-state bosonic squeezing and entanglement in a dissipative optomechanical system

“…7 and 8 show that the optimal modulation frequency is close to 2ω m , which is indeed the same as the result predicted by Eq. (37). Besides, compared to the squeezing of the mechanical oscillator position operator, the cavity-cavity entanglement has a larger scale of modulation frequency Ω, which implies that the squeezing is more sensitive to the variation of the modulation frequency.…”

“…Besides, the modulation-induced mechanical parametric amplification effectively enhances the resonant optomechanical interaction and leads to single-photon strong-coupling [30]. Remarkably, several works [31][32][33][34][35][36][37] reveal that optimizing relative ratio of optomechanical couplings, rather than simply increasing their magnitudes, is essential for achieving strong steady-state squeezing and entanglement via dissipation mechanism. These schemes exploit the Bogoliubov-mode-based method [38] instead of the Sφrensen-Mφlmer approach [39].…”

Enhanced optomechanical entanglement and cooling via dissipation engineering

“…In practical, most optomechanical systems naturally support the multimodes [4,[38][39][40], and these modes can be excited by polychromatic laser drive [41]. With the advantages of multiple degrees in multimode optomechanical systems [42], dissipation engineering [43] holds huge potential in all-optical information processing [32,44,45], where two or more mechanical or optical modes lead to a wealth of different possible schemes.…”

Reservoir-engineered entanglement in a hybrid modulated three-mode optomechanical system

“…To enhance the entanglement strength, a feasible way is to apply a suitable time modulation to the driving laser [26,27]. The method is also effective in three-mode [28][29][30] or fourmode [31,32] optomechanical systems. Another promising approach for creating strong entanglement or squeezing is to induce an effective engineered reservoir by pumping the optomechanical systems with proper blue and red detuned lasers [31][32][33][34][35][36][37][38][39][40], which is highly attractive from an experimental point of view.…”

“…The method is also effective in three-mode [28][29][30] or fourmode [31,32] optomechanical systems. Another promising approach for creating strong entanglement or squeezing is to induce an effective engineered reservoir by pumping the optomechanical systems with proper blue and red detuned lasers [31][32][33][34][35][36][37][38][39][40], which is highly attractive from an experimental point of view. As far as we know, previous studies mostly focused on enhancing entanglement between two cavity fields [33,34] or two mechanical oscillators [30][31][32][35][36][37][38].…”