Quantum entanglement between two antiferromagnets in the microcavities

Mangons are newly developed as the qubits for quantum storage and information process. Here in this work, we focus on a hybrid quantum system containing two antiferromagnets, and the entanglement between magnons in the antiferromagnets could be generated through the strong coupling mediated by the same microwave mode. Moreover, we numerically simulated the process with the feasible parameters. And the influence of the system parameters, such as the magnon-photon coupling rate, the detuning, the bias magnetic field and the dissipation on the entanglement are discussed. By adjusting some of the experimental parameters, we show that two antiferromagnets can produce a large entanglement, which is a result that has not been found in other quantum systems before. Our findings may provide a potential platform for the completion of related quantum tasks in the future.

Высокочастотный резонансный магнитоэлектрический эффект в структуре FeCoSiB-AlN на диэлектрической подложке

A high-frequency magnetoelectric (ME) effect has been discovered in a planar structure containing a ferromagnetic FeCoSiB layer and a piezoelectric AlN layer produced by magnetron sputtering on a borosilicate glass substrate. The structure was excited by a magnetic field at a frequency of the thickness acoustic vibration mode of 32.4 MHz, and the electric voltage generated by the piezoelectric layer was measured. The coefficient of ME conversion at the frequency of the second thickness mode is αE ≈ 19 V / A at a bias magnetic field of 120 A / m, corresponding to the maximum of the piezomagnetic coefficient of the ferromagnetic layer.

Self-Biased Bidomain LiNbO3/Ni/Metglas Magnetoelectric Current Sensor

The article is devoted to the theoretical and experimental study of a magnetoelectric (ME) current sensor based on a gradient structure. It is known that the use of gradient structures in magnetostrictive-piezoelectric composites makes it possible to create a self-biased structure by replacing an external magnetic field with an internal one, which significantly reduces the weight, power consumption and dimensions of the device. Current sensors based on a gradient bidomain structure LiNbO3 (LN)/Ni/Metglas with the following layer thicknesses: lithium niobate—500 μm, nickel—10 μm, Metglas—29 μm, operate on a linear section of the working characteristic and do not require the bias magnetic field. The main characteristics of a contactless ME current sensor: its current range measures up to 10 A, it has a sensitivity of 0.9 V/A, its current consumption is not more than 2.5 mA, and its linearity is maintained to an accuracy of 99.8%. Some additional advantages of a bidomain lithium niobate-based current sensor are the increased sensitivity of the device due to the use of the bending mode in the electromechanical resonance region and the absence of a lead component in the device.

A flexural mode guided wave transducer for pipes based on magnetostrictive effect

The flexural mode guided waves of pipes which are sensitive the axial crack and suitable for wave focused gain more attention recently. In this paper, a non-contact flexural mode guided wave transducer based on magnetostrictive effect is provided for pipes. Based on the magnetostrictive transduction principle and the wave structure of the flexural mode guided wave, the sensing method for generating and receiving the flexural mode guided waves based on magnetostrictive effect is obtained. According to the theoretical analysis, a non-contact magnetostrictive transducer for F (3, m) mode guided waves is given. Six permanent magnets which are evenly distributed in the circumferential direction of the pipe and arranged in opposite polarities are employed to provide the bias magnetic field in the circumferential direction. A solenoid coil is employed to induce the axial alternating magnetic field. The bias magnetic field distribution of the flexural mode guided wave in the pipeline is analyzed by the finite element simulation. The mode of the transduction guided wave in the pipe is verified by experiments based on the dispersion curves.