Single-lobe, orthonormal-beam surface emission from 2nd-order DFB/DBR lasers with half-wave grating phase shift

2003 ◽  
Author(s):  
G. Witjaksono ◽  
S. Li ◽  
D. Botez
Keyword(s):  
Phase Shift ◽  
Surface Emission ◽  
Half Wave ◽  
Beam Surface ◽  
Dbr Lasers

Single-mode and single-beam surface emission from visible red GaInP/AlGaInP laser diodes

1997 ◽  
Vol 70 (18) ◽  
pp. 2374-2376 ◽  
Author(s):  
P. O. Kellermann ◽  
A. Golshani ◽  
A. Köck ◽  
E. Gornik ◽  
H.-P. Gauggel ◽  
...  
Keyword(s):  
Laser Diodes ◽  
Single Mode ◽  
Single Beam ◽  
Surface Emission ◽  
Beam Surface

Half-Wave Cycloconverter-Based Photovoltaic Microinverter Topology With Phase-Shift Power Modulation

2013 ◽  
Vol 28 (6) ◽  
pp. 2700-2710 ◽  
Author(s):  
D. R. Nayanasiri ◽  
D. M. Vilathgamuwa ◽  
D. L. Maskell
Keyword(s):  
Phase Shift ◽  
Power Modulation ◽  
Half Wave

Broadly Wavelength Tunable DBR Lasers with Modified Multiple-Phase-Shift Super Structure Grating

1993 ◽  
Author(s):  
H. Ishii ◽  
Y. Tohmori ◽  
M. Yamamoto ◽  
T. Tamamura ◽  
Y. Yoshikuni
Keyword(s):  
Phase Shift ◽  
Super Structure ◽  
Wavelength Tunable ◽  
Multiple Phase ◽  
Dbr Lasers

Multiple-phase shift super structure grating DBR lasers for broad wavelength tuning

1993 ◽  
Vol 5 (6) ◽  
pp. 613-615 ◽  
Author(s):  
H. Ishii ◽  
Y. Tohmori ◽  
Y. Yoshikuni ◽  
T. Tamamura ◽  
Y. Kondo
Keyword(s):  
Phase Shift ◽  
Wavelength Tuning ◽  
Super Structure ◽  
Multiple Phase ◽  
Dbr Lasers

scholarly journals The X-ray evolution and geometry of the 2018 outburst of XTE J1810–197

2021 ◽  
Author(s):  
A Borghese ◽  
N Rea ◽  
R Turolla ◽  
M Rigoselli ◽  
J A J Alford ◽  
...  
Keyword(s):  
Phase Shift ◽  
Radio Pulsar ◽  
Spectral Evolution ◽  
Pulse Profile ◽  
X Ray ◽  
Monitoring Campaign ◽  
Surface Emission ◽  
Energy Dependent ◽  
Star Surface

Abstract After 15 years, in late 2018, the magnetar XTE J1810–197 underwent a second recorded X-ray outburst event and reactivated as a radio pulsar. We initiated an X-ray monitoring campaign to follow the timing and spectral evolution of the magnetar as its flux decays using Swift, XMM–Newton, NuSTAR, and NICER observations. During the year-long campaign, the magnetar reproduced similar behaviour to that found for the first outburst, with a factor of two change in its spin-down rate from ∼7.2 × 10−12 s s−1 to ∼1.5 × 10−11 s s−1 after two months. Unique to this outburst, we confirm the peculiar energy-dependent phase shift of the pulse profile. Following the initial outburst, the spectrum of XTE J1810–197 is well-modelled by multiple blackbody components corresponding to a pair of non-concentric, hot thermal caps surrounded by a cooler one, superposed to the colder star surface. We model the energy-dependent pulse profile to constrain the viewing and surface emission geometry and find that the overall geometry of XTE J1810–197 has likely evolved relative to that found for the 2003 event.

Modified multiple-phase-shift super-structure-grating DBR lasers for broad wavelength tuning

1994 ◽  
Vol 30 (14) ◽  
pp. 1141-1142 ◽  
Author(s):  
H. Ishii ◽  
Y. Tohmori ◽  
T. Tamamura ◽  
M. Yamamoto ◽  
Y. Yoshikuni
Keyword(s):  
Phase Shift ◽  
Wavelength Tuning ◽  
Super Structure ◽  
Multiple Phase ◽  
Dbr Lasers

Measuring the phase shift and polarity reversal of terahertz pulse due to half-wave loss

2011 ◽  
Author(s):  
Zhen-wei ZHANG ◽  
Kai-jun MU ◽  
Liang-liang ZHANG ◽  
Cun-lin ZHANG
Keyword(s):  
Phase Shift ◽  
Polarity Reversal ◽  
Terahertz Pulse ◽  
Half Wave

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.

A Many-Beam Technique for Enhanced Resolution of Partial Dislocations

1972 ◽  
Vol 30 ◽  
pp. 646-647
Author(s):  
J. M. Oblak ◽  
B. H. Kear
Keyword(s):  
Phase Shift ◽  
Field Method ◽  
Dark Field ◽  
Bright Field ◽  
Field Technique ◽  
Weak Beam ◽  
Partial Dislocations ◽  
Enhanced Resolution ◽  
Nickel Base ◽  
Beam Technique

The “weak-beam” and systematic many-beam techniques are the currently available methods for resolution of closely spaced dislocations or other inhomogeneities imaged through strain contrast. The former is a dark field technique and image intensities are usually very weak. The latter is a bright field technique, but generally use of a high voltage instrument is required. In what follows a bright field method for obtaining enhanced resolution of partial dislocations at 100 KV accelerating potential will be described.A brief discussion of an application will first be given. A study of intermediate temperature creep processes in commercial nickel-base alloys strengthened by the Ll2 Ni3 Al γ precipitate has suggested that partial dislocations such as those labelled 1 and 2 in Fig. 1(a) are in reality composed of two closely spaced a/6 <112> Shockley partials. Stacking fault contrast, when present, tends to obscure resolution of the partials; thus, conditions for resolution must be chosen such that the phase shift at the fault is 0 or a multiple of 2π.

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