scholarly journals Orbital alignment cross sections by stimulated emission probing: The state‐to‐state Ca Rydberg process Ca(4s17d 1D2)+Xe→Ca(4s18p 1P1)+Xe

1995 ◽  
Vol 102 (24) ◽  
pp. 9532-9536 ◽  
Author(s):  
Eileen M. Spain ◽  
Mark J. Dalberth ◽  
Paul D. Kleiber ◽  
Stephen R. Leone ◽  
Stefan S. Op de Beek ◽  
...  
Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 431
Author(s):  
Giorgio Turri ◽  
Scott Webster ◽  
Michael Bass ◽  
Alessandra Toncelli

Spectroscopic properties of neodymium-doped yttrium lithium fluoride were measured at different temperatures from 35 K to 350 K in specimens with 1 at% Nd3+ concentration. The absorption spectrum was measured at room temperature from 400 to 900 nm. The decay dynamics of the 4F3/2 multiplet was investigated by measuring the fluorescence lifetime as a function of the sample temperature, and the radiative decay time was derived by extrapolation to 0 K. The stimulated-emission cross-sections of the transitions from the 4F3/2 to the 4I9/2, 4I11/2, and 4I13/2 levels were obtained from the fluorescence spectrum measured at different temperatures, using the Aull–Jenssen technique. The results show consistency with most results previously published at room temperature, extending them over a broader range of temperatures. A semi-empirical formula for the magnitude of the stimulated-emission cross-section as a function of temperature in the 250 K to 350 K temperature range, is presented for the most intense transitions to the 4I11/2 and 4I13/2 levels.


2021 ◽  
Vol 36 (1) ◽  
pp. 33-59
Author(s):  
Jim van der Meulen

AbstractThis article charts the long-term development of seigneurial governance within the principality of Guelders in the Low Countries. Proceeding from four quantitative cross-sections (c. 1325, 1475, 1540, 1570) of seigneurial lordships, the conclusion is that seigneurial governance remained stable in late medieval Guelders. The central argument is that this persistence of seigneurial governance was an effect of active collaboration between princely administrations, lords, and local communities. Together, the princely government and seigneuries of Guelders formed an integrated, yet polycentric, state. The article thereby challenges the narrative of progressive state centralisation that predominates in the historiography of pre-modern state formation.


1989 ◽  
Vol 14 (16) ◽  
pp. 856 ◽  
Author(s):  
R. Beach ◽  
S. Weinzapfel ◽  
R. Staver ◽  
R. Solarz ◽  
M. Shinn ◽  
...  

2021 ◽  
Vol 2086 (1) ◽  
pp. 012175
Author(s):  
A Volokitina ◽  
P Loiko ◽  
E Dunina ◽  
A Kornienko ◽  
J M Serres ◽  
...  

Abstract Polarization anisotropy of luminescent properties of europium (III) ions in low-symmetry C2 sites is studied using monoclinic (sp. gr. C2/c) tungstate crystal KY(WO4)2. The 5D0 → 7FJ (where J = 0…6) transitions are characterized for the principal light polarizations. Polarization selection rules for the magnetic dipole 5D0 → 7F1 transition are presented. The stimulated-emission cross-sections for Eu3+ ions relevant for laser operation are determined.


Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 443 ◽  
Author(s):  
Hongyan Xia ◽  
Chang Hu ◽  
Tingkuo Chen ◽  
Dan Hu ◽  
Muru Zhang ◽  
...  

This paper provides a review of advances in conjugated polymer lasers. High photoluminescence efficiencies and large stimulated emission cross-sections coupled with wavelength tunability and low-cost manufacturing processes make conjugated polymers ideal laser gain materials. In recent years, conjugated polymer lasers have become an attractive research direction in the field of organic lasers and numerous breakthroughs based on conjugated polymer lasers have been made in the last decade. This paper summarizes the recent progress of the subject of laser processes employing conjugated polymers, with a focus on the photoluminescence principle and excitation radiation mechanism of conjugated polymers. Furthermore, the effect of conjugated polymer structures on the laser threshold is discussed. The most common polymer laser materials are also introduced in detail. Apart from photo-pumped conjugated polymer lasers, a direction for the future development of electro-pumped conjugated polymer lasers is proposed.


1937 ◽  
Vol 10 (4) ◽  
pp. 778-786
Author(s):  
R. Ariano

Abstract The results of tests of the brittleness of ebonite are described. Resilience is influenced chiefly by the moment of inertia of the cross section of the test-specimen, but it seems also to be affected by the form of the specimen. The state of vulcanization has considerable influence on these mechanical properties within the undercured range, but with thorough vulcanization the state of cure plays no appreciable part. Notching of test-specimens is not of great importance. It diminishes the resilience, but when the tests are compared on a basis of equal moments of inertia of the resistant cross sections, this diminution becomes inappreciable in the case of brittle ebonites. On the other hand, the shape of the notch in ebonites containing no loading ingredients does influence the resilience. With V-shaped notches, the depth of the notch and its angle of aperture influence considerably the resilience of this latter type of ebonite, and notches of minimum depth are sufficient to have an appreciable effect.


2021 ◽  
Vol 129 (12) ◽  
pp. 1484
Author(s):  
Е.А. Серегина ◽  
А.А. Серегин ◽  
Г.В. Тихонов

The spectra of absorption, luminescence, and lifetime of Yb3+ in SO2Cl2 – GaCl3 – Yb3+ solutions were measured. Information is obtained on the Stark splitting of energy levels, absorption and stimulated emission cross sections of Yb3+. An analysis of the spectral dependence of the gain cross sections indicates that the SOCl2 – GaCl3 – Yb3 solution is promising as the active medium of a diode-pumped liquid ytterbium laser.


Sign in / Sign up

Export Citation Format

Share Document