Controllable chiral Majorana modes by noncollinear magnetic configuration in a topological Josephson junction

Recently, theory and experiment both have confirmed a Majorana zero mode to induce selective equal spin Andreev reflection (SESAR). Herein, we theoretically present controllable chiral Majorana modes (CMMs) by noncollinear magnetic configuration in a Josephson junction on a topological insulator with two ferromagnetic insulators (FIs) sandwiched in between two superconductors (SCs). It is shown that an additional phase shift is induced by the different chirality of the CMMs at the two FI/SC interfaces, whose magnitude is determined by misorientational angle θ, which can be administrated by the Andreev bound surface energies. The angle θ is found to result in the 0-π state transition and Φ0 supercurrent. Particularly, due to the SESAR, the coexistence of fully spin-polarized spin-singlet and -triplet correlations is exhibited with the exclusive fully spin-polarized spin-triplet (singlet) correlation corresponding to the ferromagnetic (F) [antiferromagnetic (AF)] configuration. For the two magnetizations only along y-axis, there exist no additional phase shift and topological supercurrent with fully spin-polarized correlations, especially, the supercurrent in the AF configuration is a lot larger than that in the F one, which is strongly dependent on the exchange field strength and FI length, thus even leading to 100% supercurrent magnetoresistance. The results can be employed to not only identify the topological SCs but also design a perfect topological supercurrent spin valve device.

Fluctuations out of equilibrium

A generalized fluctuation–dissipation theorem involving slowly varying parameters is presented. Application of the Langevin method, the method of moments and of a multiscale technique reveal that not only dissipation but also dispersive contributions determine the spectral functions of fluctuations in arbitrary statistical systems. The non-Joule dispersive contribution is characterized by a novel non-local effect due to the additional phase shift between the force and the response of the system. This phase shift occurs as a result of parametric control to the system. The general formalism is illustrated by concrete examples and applications. This article is part of the theme issue ‘Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 2)’.

Semiconductor rectifier with side pulsation

Described rectifier with twelve output voltage ripple is designed to supply industrial load and power lines DC, and provides savings in material and installation cost savings. A scheme managed rectifier with side pulsations, which gives a gain of up to 30% on mass and dimensions compared to classical schemes with two secondary windings are star-delta and provides better electromagnetic compatibility with the mains. The essence of the method is that the amount of segments of two sine waves results in a segment as a sinusoidal function to the amplitude and phase determined by the amplitude and phase terms. In the case of controlled semiconductor valves in a three-phase bridge circuit, it is possible to obtain an additional phase shift - at the expense of the control algorithm, which is the subject of this article. The total voltage of the two series-connected three-phase bridges (second - controlled with the "side pulsation ") connected to two secondary windings supplying three-phase transformer with a ratio of the number of turns in a ratio of 2.8: 1, respectively, and the same method of switching the two secondary windings with star connection has 12 pulsations.

A Phase Anti-Ambiguity Method for USBL System

Target localization was generally achieved by range and azimuth measurement for USBL (Ultra-Short Base Line) positioning system, of which the positioning accuracy was restrained by the array aperture. It usually adopted redundant array elements to solve the inconsistence between high precision and phase ambiguity. However, this routine would introduce the additional phase shift calibration problem for the complex and asymmetric array elements, which was not easy to get good results. To solve this problem, an anti-ambiguity method called dual-pulse signal is proposed in this paper to ensure the correct positioning for the improved array formation. Numerical simulations indicate that the proposed method can effectively improve the positioning precision of the USBL positioning system.

The Method for Improving the USBL Positioning System

This paper addresses a problem of estimating the precision phase-shift between the transducers of an Ultra short baseline (USBL) array. Due to fact that the performance of the traditional USBL system would evidently decline as the position error increases with the range, the paper at first proposed a high-precision positioning algorithm applied to an improved array to overcome this problem. Besides, employing a least-squares method, the additional phase shift between the transducers are also considered to be determined experimentally by rotating the USBL array in an acoustic test tank, which furthermore reduces the phase shift measuring error. Some trials results show that the proposed high-precision algorithm with improved array can be achieved with good accuracy, as well as the alignment phase shift offset.

Mechanism of the long-wave inertialess instability of a two-layer film flow

This paper provides an intuitive interpretation of the long-wave inertialess instability of a two-layer film flow. The underlying mechanism is elucidated by inspecting the longitudinal perturbation velocity associated with the surface and interfacial deflections. The velocity is expressed by the composition of three parts, related to the shear stress at the free surface, the continuity condition at the interface, and the pressure disturbance induced by gravity. The effect of each velocity component on the evolutions of the surface and the interface is examined in detail. Specifically, the growth of the free surface is caused by the continuity-induced first-order velocity disturbance associated with an additional phase shift between the surface and interfacial waves, while the growth of the interface is due to the pressure-driven flow. The proposed mechanism gives an alternatively reliable prediction of the wave velocity and growth rate.