ISSN:
1432-0630
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The pentaphosphate system Nd1−x Y x P5O14 covers four crystalline phases with five different site geometries for Nd. We determined the4F3/2,4I13/2,4I11/2,4I9/2 stark levels and identified the sites spectroscopically, including the case of the monoclinic layer structureC2/c which has two Nd sites. Crystal field calculations for the energy levels in the monoclinic phaseP2 1/c and the orthorhombic phasepnma with tetragonal and orthorhombic site symmetry approximations are reasonable but reveal their shortcomings. As a consequence, we consider it improper to try to calculate rare-earth optical transition probabilities with approximate crystal fields. Random distribution of Nd and Y causes inhomogeneous broadening (∼6 Å) which peaks atx=0.5. Thermal equilibrium between the4F3/2 levels is reached within 2–5×10−13 sec. The three room temperature modifications could be lased cw. Pure NdP5O14 was found to be the best laser.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00896620
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