We theoretically propose a scheme to realize a $n$-cavity-magnon polariton blockade in a cavity-magnon system by utilizing the Kerr nonlinearity. Cavity-magnon polaritons are hybrid quasiparticles formed by the strong coupling between cavity photons and magnons. The Kerr nonlinearity introduces anharmonicity into the polariton energy spectrum, which in turn enables the blockade effect. We demonstrate that when the external driving frequency is resonant with the transition to the $n$th polariton excited state, a perfect $n$-polariton blockade is achieved. Moreover, increasing the driving strength enhances higher-order blockade while maintaining high purity. Our work pioneers the field of cavity-magnon polariton blockade, opens a new avenue for the preparation of controllable quantum resources and holds significant potential for applications in the fields of quantum communication and quantum information processing.
We theoretically propose a scheme to realize a n-cavity-magnon polariton blockade in a cavity-magnon system by utilizing the Kerr nonlinearity. Cavity-magnon polaritons are hybrid quasiparticles formed by the strong coupling between cavity photons and magnons. The Kerr nonlinearity introduces anharmonicity into the polariton energy spectrum, which in turn enables the blockade effect. We demonstrate that when the external driving frequency is resonant with the transition to the nth polariton excited state, a perfect n-polariton blockade is achieved. Moreover, increasing the driving strength enhances higher-order blockade while maintaining high purity. Our work pioneers the field of cavity-magnon polariton blockade, opens a new avenue for the preparation of controllable quantum resources and holds significant potential for applications in the fields of quantum communication and quantum information processing.
The quantum blockade effect is one of the important control methods for various quantum states. Recently, magnon has gradually become the focus of quantum device research due to its excellent properties such as stability, high spin density, and tunability. This study investigates the generation of conventional and unconventional single and double magnon blockades, as well as magnon-induced tunneling effects, in strongly nonlinearly coupled cavity–magnon systems. By adjusting the coupling strength and the driving field, we achieved single and double magnon blockades, along with magnon-induced tunneling effects. Interestingly, we found that the transition from a magnon blockade to magnon-induced tunneling can be controlled by modulating the driving field. To validate the feasibility of our model, we examined the impact of thermal noise at an experimental temperature of 20 mK. Our proposed scheme may offer a method to manipulate few-magnon states and holds potential applications in quantum communication and quantum information processing.
Magnon blockade is an effective physical mechanism to generate a single magnon, which is of great importance in quantum information processing. We present a scheme to realize the unconventional magnon blockade effect by using Kerr nonlinearity in a cavity electromagnonic system. Under weak driving conditions, we give the optimal parameter conditions for magnon antibunching through analytical calculations, which are in good agreement with numerical results. Furthermore, we find that Kerr nonlinearity is necessary to create magnon blockade. In particular, unconventional magnon blockade can be achieved in both weak nonlinearity and weak coupling regimes. The present scheme indicates a method for generating unconventional magnon blockade effect and provides a feasible and flexible platform for the realization of a single-magnon source with high purity.
Strong coupling between single qubits is crucial for quantum information science and quantum computation. However, it is still challenged, especially for single solid-state qubit. Here, we propose a hybrid quantum system, consisting of a coplanar waveguide (CPW) resonator weakly coupled to a single nitrogen-vacancy spin in diamond and a yttrium-iron-garnet (YIG) nanosphere holding Kerr magnons, to realize strong long-distance spin-spin coupling. With a strong driving field on magnons, the Kerr effect can squeeze magnons, and {thus the coupling between the CPW resonator and the sequeezed magnons is exponentially enhanced}, which produces two cavity-magnon polaritons, i.e., the high-frequency polariton (HP) and low-frequency polariton (LP). When the enhanced cavity-magnon coupling {approaches} the critical value (i.e., the frequency of the LP becomes zero), the spin is fully decoupled from the HP, while the coupling between the spin and the LP is significantly improved. In the dispersive regime, a strong spin-spin coupling mediated by the LP is achieved with accessible parameters. Our proposal indicates that the critical cavity-magnon polarition is a potential interface to realize strong spin-spin coupling and manipulates remote solid spins.
Strong coupling between single qubits is crucial for quantum information science and quantum computation. However, it is still challenged, especially for single solid-state qubit. Here, we propose a hybrid quantum system, consisting of a coplanar waveguide (CPW) resonator weakly coupled to a single nitrogen-vacancy (NV) spin in diamond and an yttrium-iron-garnet (YIG) nanosphere holding Kerr magnons, to realize strong long-distance spin-spin coupling. With a strong driving field on magnons, the Kerr effect can squeeze magnons, and thus the coupling between the CPW resonator and the squeezed magnons is exponentially enhanced, which produces two cavity-magnon polaritons, i.e., the high-frequency polariton (HP) and the low-frequency polariton (LP). When the enhanced cavity-magnon coupling approaches the critical value (i.e., the frequency of the LP becomes zero), the spin is fully decoupled from the HP, while the coupling between the spin and the LP is significantly improved. In the dispersive regime, a strong spin-spin coupling mediated by the LP is achieved with accessible parameters. Our proposal indicates that the critical cavity-magnon polariton is a potential interface to realize strong spin-spin coupling and manipulates remote solid spins.
Strong coupling between single qubits is crucial for quantum information science and quantum computation. However, it is still challenged, especially for single solid-state qubit. Here, we propose a hybrid quantum system, consisting of a coplanar waveguide (CPW) resonator weakly coupled to a single nitrogen-vacancy spin in diamond and a yttrium-iron-garnet (YIG) nanosphere holding Kerr magnons, to realize strong long-distance spin-spin coupling. With a strong driving field on magnons, the Kerr effect can squeeze magnons, and {thus the coupling between the CPW resonator and the sequeezed magnons is exponentially enhanced}, which produces two cavity-magnon polaritons, i.e., the high-frequency polariton (HP) and low-frequency polariton (LP). When the enhanced cavity-magnon coupling {approaches} the critical value (i.e., the frequency of the LP becomes zero), the spin is fully decoupled from the HP, while the coupling between the spin and the LP is significantly improved. In the dispersive regime, a strong spin-spin coupling mediated by the LP is achieved with accessible parameters. Our proposal indicates that the critical cavity-magnon polarition is a potential interface to realize strong spin-spin coupling and manipulates remote solid spins.
Strong coupling between single qubits is crucial for quantum information science and quantum computation. However, it is still challenged, especially for single solid-state qubit. Here, we propose a hybrid quantum system, consisting of a coplanar waveguide (CPW) resonator weakly coupled to a single nitrogen-vacancy spin in diamond and a yttrium-iron-garnet (YIG) nanosphere holding Kerr magnons, to realize strong long-distance spin-spin coupling. With a strong driving field on magnons, the Kerr effect can squeeze magnons, and {thus the coupling between the CPW resonator and the sequeezed magnons is exponentially enhanced}, which produces two cavity-magnon polaritons, i.e., the high-frequency polariton (HP) and low-frequency polariton (LP). When the enhanced cavity-magnon coupling {approaches} the critical value (i.e., the frequency of the LP becomes zero), the spin is fully decoupled from the HP, while the coupling between the spin and the LP is significantly improved. In the dispersive regime, a strong spin-spin coupling mediated by the LP is achieved with accessible parameters. Our proposal indicates that the critical cavity-magnon polarition is a potential interface to realize strong spin-spin coupling and manipulates remote solid spins.