Object Wave Determination by Single-Sideband Methods

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.

The Method for Improving the USBL Positioning System

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.

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

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.

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

2021 ◽  
Author(s):  
MengYao Li ◽  
Qingyun Yu ◽  
Jingguo Hu ◽  
TingMin Liu ◽  
Yong Chun Tao ◽  
...  
Keyword(s):  
Phase Shift ◽  
Josephson Junction ◽  
Spin Valve ◽  
Magnetic Configuration ◽  
Spin Singlet ◽  
Spin Polarized ◽  
Spin Triplet ◽  
Majorana Modes ◽  
Additional Phase Shift ◽  
Additional Phase

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.

Heavy Atom Clusters as Specific Labels

1988 ◽  
Vol 46 ◽  
pp. 238-239
Author(s):  
James F. Hainfeid
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Active Site ◽  
Heavy Atom ◽  
Carbon Films ◽  
Heavy Atoms ◽  
Single Atoms ◽  
Atom Clusters ◽  
Thin Carbon ◽  
Important Milestone

An important milestone in electron microscopy was the first visualization of single atoms in 1970 with the STEM designed by Albert Crewe. This achievement inspired thoughts that single heavy atoms could be used as super high resolution labels of biological structures by, for example, covalently reacting a heavy atom reagent at the active site of an enzyme. Further investigation of heavy atoms on thin carbon films revealed that they hopped about and that this was not solely thermal motion, but beam induced, since cooling the specimen had little effect. Attempts were made to try various heavy atom compounds but alas, these all behaved similarly, with about 10% of the atoms moving 3-10 Å on successive scans. A gallant effort by M. Beer to sequence DNA using heavy atom base specific labels befell similar problems where the motion of the label prevented high resolution coordinates from being measured.

Heavy Atom Cluster Labeling of Biological Specimens

1985 ◽  
Vol 43 ◽  
pp. 718-719
Author(s):  
J.J. Lipka ◽  
J.F. Hainfeld ◽  
J.S. Wall
Keyword(s):  
Heavy Metal ◽  
Heavy Atom ◽  
Carbon Films ◽  
Cluster Labeling ◽  
Heavy Atoms ◽  
Glycoprotein Complex ◽  
Thin Carbon ◽  
Lysine Residues ◽  
Cluster Ion ◽  
Beam Dose

The Brookhaven STEM is capable of resolving single heavy atoms deposited on thin carbon films with a beam dose > 103 el Å-2 Single heavy atoms, therefore, are unsuitable as fiducial markers on unordered biological specimens because of the high beam dose required for direct visualization. Heavy metal-clusters or heavy metal-containing complexes have been resolved at much lower beam doses, as low as 30 el Å-2, and therefore may be useful as directly visible labels.The polyamine undecagold (11-Au) cluster ion, [(p-H2NCH2C6H4)3P]7 Au113+, has been used to covalently label the carbohydrate sites of the glycoprotein complex of human haptoglobin hemoglobin (Hp˙Hb) by a route which should be general for any glycoprotein with oxidizable carbohydrate residues. Proteins with reactive lysine residues have been covalently 11-Au labeled by the reactions noted in Scheme 1.

scholarly journals Fluctuations out of equilibrium

2018 ◽  
Vol 376 (2135) ◽  
pp. 20170383 ◽  
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)’.

Small-Signal Analysis of Parallel Connected Voltage Source Inverters Using a Frequency and Voltage Droop Control Including an Additional Phase Shift

2014 ◽  
Vol 25 (5) ◽  
pp. 597-607 ◽  
Author(s):  
Wanderley Alves Parreira ◽  
Henrique José Avelar ◽  
João Batista Vieira ◽  
Luiz Carlos Freitas ◽  
Luiz Carlos Gomes de Freitas ◽  
...  
Keyword(s):  
Phase Shift ◽  
Signal Analysis ◽  
Voltage Source ◽  
Droop Control ◽  
Small Signal ◽  
Voltage Source Inverters ◽  
Small Signal Analysis ◽  
Additional Phase Shift ◽  
Additional Phase

Intrinsic phase response characterization of optical filters free of additional phase shift from pigtail or free space

2020 ◽  
Vol 59 (01) ◽  
pp. 1
Author(s):  
Fei Yuan ◽  
Yaowen Zhang ◽  
Zhiyao Zhang ◽  
Shanjian Zhang ◽  
Yali Zhang ◽  
...  
Keyword(s):  
Phase Shift ◽  
Free Space ◽  
Optical Filters ◽  
Phase Response ◽  
Additional Phase Shift ◽  
Additional Phase
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