Phase-controlled robust tripartite quantum entanglement in cavity-magnon optomechanics

The preparation of highly entangled states involving multiparticle systems is of crucial importance in quantum physics, playing a fundamental role in exploring the nature of quantum mechanics and offering essential quantum resources for nascent quantum technologies that surpass classical limits. Here we present how to generate and manipulate tripartite entangled state of photons, phonons, and magnons within a hybrid cavity magnomechanical system. It is shown that by simultaneously applying two coherent driving fields to this system in opposite input directions, it enables a coherent and effective way to regulate the magnomechanical interaction by tuning the phase difference of the driving fields. Based on this feature, it is found that the tripartite entanglement also becomes phase-dependent and can be enhanced for certain phase difference. More interestingly, it is shown that the robustness of tripartite entanglement against environmental thermal noises can also be improved by choosing proper phase difference of the driving fields. Our findings open up a promising way to manipulate and protect fragile tripartite entanglement, which is applicable to a wide range of quantum protocols that require multipartite entangled resources such as quantum communication and quantum metrology.