Relativistic mean-field study of odd-AN and F isotopes

Abstract

The ground-state properties of odd-A N and F isotopes are calculated using the nonlinear relativistic mean-field theory with NL-SH and NL1 force parameters. Reasonable agreement with experimental data of binding energies is achieved even for nuclei near the neutron-drip line. Neutron halos in 23 N and 25, 27, 29 F are predicted.

Discussion on the origin of NIR emission from Bi-doped materials

“…While some of the experimental and theoretical observations in relation to Bi 5+ species appear very convincing, a large amount of parallel experimental data strongly contradicts the possibility that Bi 5+ or related species may be the origin of NIR emission [3,[6][7][8][9][10][11][12][13][14][15][17][18][19][22][23][24][25][26][27][28][29][30]. In this context, the following experimental, partly phenomenological facts have to be noted:…”

“…As the NIR emission origin, they suggested the transition X 2 2 Π 3/2 → X 1 2 Π 1/2 in BiO molecules dispersed in the glass [41]. However, successive work on Bi-doped chalcogenide glass rejected this possibility because of the absence of oxygen [25].…”

“…Since then, research on Bi-doped NIR-emitting glasses, crystals and optical devices has experienced rapid growth and is now conducted in laboratories on almost every continent. NIR emission from bismuthbased centers has successively been reported for silicate [1,2,[5][6][7][8][9][10][11][12][13][14][15][16], germanate [3,7,[17][18][19][20][21], aluminoborate [22], aluminophosphate [23,24], chalcogenide [25][26][27][28], germanosilicate [29,30], aluminosilicate [6,9,31] and borosilicate glasses [31,32] as well as for polycrystalline SrB 4 O 7 [8], single crystals of RbPb 2 Cl 5 [33], BaF 2 [34], α-BaB 2 O 4 [35] and various other materials. Also on the area of device fabrication, progress has been very rapid.…”

“…Surprisingly, the nature of this NIR photoluminescence is still unknown, although many hypotheses have been formulated, attributing emission to Bi 5+ [37][38][39][40], Bi-clusters [17], Bi + [22,23,25,26,28,34,35], BiO [8,31,41], dimer ions Bi 2 , Bi 2 − and Bi 2 2− [11,12,24,42], Bi 0 [43,44], molecular orbital models [40,45,46] or even point defects [21]. In the present paper, all these attempts to clarify the origin of NIR emission will be critically evaluated with the goal to condense the accumulated information into a potential resolution of the problem, and to identify directions for future research.…”

Structural impact of iron ions on BaBiBO4 glasses: Spectroscopic and dielectric investigations

“…Bismuth borate glasses have been proposed as gain medium for ultra broad band fiber amplifiers [1][2][3][4]. In subsequent experiments, optical amplification, laser output, tunable laser operation, and allfiber lasers were demonstrated based on Bi containing glasses [5][6][7]. More recently, Bi-doped glasses were further considered for the usage of spectral converters and planar luminescent concentrators for photovoltaic energy conversion using low band gap semiconductors, ultra fast optical switches because of their long infrared cutoff and high third order nonlinear optical susceptibility [8].…”