The direct coupling system between a magnon and a superconducting qubit exhibits a special advantage in the quantum information processing [Phys. Rev. Lett. 129, 037205 (2022) ]. In this paper, based on this direct coupling system, the magnonic squeezed Schr\"odinger cat states (MSSCSs) can be generated by the conditional displacement mechanism. Numerical simulation shows that our scheme is robust to the dissipation of the system. In particular, we find that the coherence amplitude of MSSCSs can be enhanced via a squeezed transformation. Our results have potential application in quantum information processing and quantum optics.The direct coupling system between a magnon and a superconducting qubit exhibits a special advantage in the quantum information processing [Phys. Rev. Lett. 129, 037205 (2022) ]. In this paper, based on this direct coupling system, the magnonic squeezed Schr\"odinger cat states (MSSCSs) can be generated by the conditional displacement mechanism. Numerical simulation shows that our scheme is robust to the dissipation of the system. In particular, we find that the coherence amplitude of MSSCSs can be enhanced via a squeezed transformation. Our results have potential application in quantum information processing and quantum optics.

Physical Review ANov 13, 20247 citations

Generation of Number-Phase Squeezed States

Gunnar G. Bjork, Olle Nilsson, Y. Yamamoto +1 more

NATO ASI series. Series B : PhysicsJan 1, 19894 citations

Superradiant phase transition induced by the indirect Rabi interaction

Wen Huang, Ying Wu, Xin‐You Lü

We theoretically study the superradiant phase transition (SPT) in an indirect Rabi model, where both a two-level system and a single-mode bosonic field couple to an auxiliary bosonic field. We find that the indirect spin-field coupling induced by the virtual excitation of the auxiliary field can allow the occurrence of a SPT at a critical point, and the influence of the so-called ${A}^{2}$ term in the normal Rabi model is naturally avoided. In the large detuning regime, we present the analytical expression of quantum critical point in terms of the original system parameters. The critical atom-field coupling strength is tunable, which will loosen the conditions on realizing the SPT. Considering a hybrid magnon-cavity-qubit system, we predict the squeezed cat state of magnon generated with feasible experimental parameters, which has potential applications in quantum metrology and quantum information processing.We theoretically study the superradiant phase transition (SPT) in an indirect Rabi model, where both a two-level system and a single-mode bosonic field couple to an auxiliary bosonic field. We find that the indirect spin-field coupling induced by the virtual excitation of the auxiliary field can allow the occurrence of a SPT at a critical point, and the influence of the so-called ${A}^{2}$ term in the normal Rabi model is naturally avoided. In the large detuning regime, we present the analytical expression of quantum critical point in terms of the original system parameters. The critical atom-field coupling strength is tunable, which will loosen the conditions on realizing the SPT. Considering a hybrid magnon-cavity-qubit system, we predict the squeezed cat state of magnon generated with feasible experimental parameters, which has potential applications in quantum metrology and quantum information processing.

arXiv:2302.07506Physical Review AMar 3, 20236 citations

Generating number-phase squeezed states

Matthew J. Collett

Springer eBooksDec 4, 20070 citations

Experimental Generation of Squeezed Cat States with an Operation Allowing Iterative Growth

Jean Etesse, Martin Bouillard, Bhaskar Kanseri +1 more

We present what is, to our knowledge, the first implementation of a "cat breeding" operation, which allows an iterative growth of cat states. We thus report the experimental generation of a squeezed cat state from two single photon Fock states, which can be seen as cat states with zero amplitude. These Fock states are mixed on a symmetrical beam splitter, and the generation is heralded by a homodyne measurement in one of the two output arms. The output state has a fidelity of 61% with an even squeezed cat state of amplitude α=1.63. This hybrid operation opens up new prospects in quantum optics, as the protocol depicted here can be iterated in order to produce new kinds of mesoscopic states.We present what is, to our knowledge, the first implementation of a "cat breeding" operation, which allows an iterative growth of cat states. We thus report the experimental generation of a squeezed cat state from two single photon Fock states, which can be seen as cat states with zero amplitude. These Fock states are mixed on a symmetrical beam splitter, and the generation is heralded by a homodyne measurement in one of the two output arms. The output state has a fidelity of 61% with an even squeezed cat state of amplitude α=1.63. This hybrid operation opens up new prospects in quantum optics, as the protocol depicted here can be iterated in order to produce new kinds of mesoscopic states.

Physical Review LettersMay 15, 2015125 citations

{A}^{2}

term in the normal Rabi model is naturally avoided. In the large detuning regime, we present the analytical expression of quantum critical point in terms of the original system parameters. The critical atom-field coupling strength is tunable, which will loosen the conditions on realizing the SPT. Considering a hybrid magnon-cavity-qubit system, we predict the squeezed cat state of magnon generated with feasible experimental parameters, which has potential applications in quantum metrology and quantum information processing.