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

Abstract 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.

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Object Wave Determination by Single-Sideband Methods

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071776 ◽

1973 ◽

Vol 31 ◽

pp. 266-267

Author(s):

Kenneth H. Downing ◽

Benjamin M. Siegel

Keyword(s):

Phase Shift ◽

Carbon Films ◽

Object Wave ◽

Electron Wave ◽

Phase Object ◽

Heavy Atoms ◽

Single Sideband ◽

Thin Carbon ◽

Additional Phase Shift ◽

Additional Phase

Under the “weak phase object” approximation, the component of the electron wave scattered by an object is phase shifted by π/2 with respect to the unscattered component. This phase shift has been confirmed for thin carbon films by many experiments dealing with image contrast and the contrast transfer theory. There is also an additional phase shift which is a function of the atomic number of the scattering atom. This shift is negligible for light atoms such as carbon, but becomes significant for heavy atoms as used for stains for biological specimens. The light elements are imaged as phase objects, while those atoms scattering with a larger phase shift may be imaged as amplitude objects. There is a great deal of interest in determining the complete object wave, i.e., both the phase and amplitude components of the electron wave leaving the object.

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The Method for Improving the USBL Positioning System

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 4 ◽

10.1115/omae2010-20762 ◽

2010 ◽

Author(s):

Yu Min

Keyword(s):

Phase Shift ◽

High Precision ◽

Good Accuracy ◽

Least Squares Method ◽

Measuring Error ◽

Short Baseline ◽

Precision Phase ◽

Positioning Algorithm ◽

Additional Phase Shift ◽

Additional Phase

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.

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Applications of the Transit-Time Current — Voltage Relationships to Negative — Conductance Devices

International Journal of Electrical Engineering Education ◽

10.1177/002072097501200415 ◽

1975 ◽

Vol 12 (4) ◽

pp. 328-337

Author(s):

Y. W. Lam

Keyword(s):

Phase Shift ◽

Transit Time ◽

Carrier Injection ◽

Avalanche Diode ◽

Current Voltage ◽

Injection Mechanism ◽

Negative Conductance ◽

Additional Phase Shift ◽

Additional Phase

The current-voltage relationships developed in the previous paper is applied to two examples: the transistor transit-time oscillator and the Read avalanche diode. It is shown that transit time in the semiconductor alone is insufficient to create negative conductance which is essential for oscillation to take place. Instead additional phase shift must be introduced. In both examples treated in this paper, the additional phase shift comes from the carrier-injection mechanism.

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Switchable Spiral Josephson junction: A superconducting spin-valve proposal

Superconductor Science and Technology ◽

10.1088/1361-6668/ac3f9f ◽

2021 ◽

Author(s):

Nataliya Pugach ◽

Dennis Heim ◽

Dmitriy Seleznyov ◽

Alexander Chernov ◽

Dirk Menzel

Keyword(s):

Josephson Junction ◽

Critical Current ◽

Barrier Layer ◽

Ground State ◽

Spin Valve ◽

Barrier Material ◽

Spiral Magnet ◽

Magnetic Metal ◽

Spin Triplet ◽

And Control

Abstract We propose a superconducting spin valve based on a Josephson junction with B20-family magnetic metal as barrier material. Our analysis shows that the states of this element can be switched by reorienting the intrinsic non-collinear magnetization of the spiral magnet. This reorientation modiﬁes long-range spin-triplet correlations and thereby inﬂuences strongly the critical Josephson current. Compared to superconducting spin valves proposed earlier, our device has the following advantages: (i) it contains only one barrier layer, which makes it easier to fabricate and control; (ii) its ground state is stable, which prevents uncontrolled switching; (iii) it is compatible with devices of low-T Josephson electronics. This device may switch between two logical states which exhibit two different values of critical current, or its positive and negative value. I.e. 0-π switch is achievable on one simple Josephson junction.

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Anomalous anisotropic behaviour of spin-triplet proximity effect in Au/SrRuO3/Sr2RuO4 junctions

Scientific Reports ◽

10.1038/s41598-019-52003-0 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

M. S. Anwar ◽

M. Kunieda ◽

R. Ishiguro ◽

S. R. Lee ◽

C. Sow ◽

...

Keyword(s):

Proximity Effect ◽

Magnetic Inhomogeneity ◽

Anisotropic Behaviour ◽

Electronic Spin ◽

Anisotropic Field ◽

Spin Singlet ◽

Spin Polarized ◽

Field Response ◽

Spin Triplet ◽

Triplet Correlation

Abstract Spin-polarized supercurrents can be generated with magnetic inhomogeneity at a ferromagnet/spin-singlet-superconductor interface. In such systems, complex magnetic inhomogeneity makes it difficult to functionalise the spin-polarized supercurrents. However, spin-polarized supercurrents in ferromagnet/spin-triplet-superconductor junctions can be controlled by the angle between magnetization and spin of Copper pairs (d-vector), that can effectively be utilized in developing of a field of research known as superconducting spintronics. Recently, we found induction of spin-triplet correlation into a ferromagnet SrRuO3 epitaxially deposited on a spin-triplet superconductor Sr2RuO4, without any electronic spin-flip scattering. Here, we present systematic magnetic field dependence of the proximity effect in Au/SrRuO3/Sr2RuO4 junctions. It is found that induced triplet correlations exhibit strongly anisotropic field response. Such behaviour is attributed to the rotation of the d-vector of Sr2RuO4. This anisotropic behaviour is in contrast with the vortex dynamic. Our results will stimulate study of interaction between ferromagnetism and unconventional superconductivity.

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Additional phase shift effect in acousto-optic interaction and its applications

10.1117/12.131924 ◽

1992 ◽

Cited By ~ 1

Author(s):

Vladimir I. Balakshy

Keyword(s):

Phase Shift ◽

Acousto Optic Interaction ◽

Shift Effect ◽

Additional Phase Shift ◽

Additional Phase

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Fluctuations out of equilibrium

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2017.0383 ◽

2018 ◽

Vol 376 (2135) ◽

pp. 20170383 ◽

Cited By ~ 1

Author(s):

V. V. Belyi

Keyword(s):

Phase Shift ◽

Dissipative Structures ◽

Local Effect ◽

Spectral Functions ◽

Fluctuation Dissipation ◽

Fluctuation Dissipation Theorem ◽

Non Local ◽

Statistical Systems ◽

Additional Phase Shift ◽

Additional Phase

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)’.

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