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1

Diamond side resonances: influence of isotopic substitution of carbon

Ivanov A. A., Ivanov A. I.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2017

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Vol. 21, No 2

173--176

EN

We discuss the side resonances of the optically detected magnetic resonance in a diamond crystal and propose a new approach to the calculation of the hyperfine interaction in a composed system consisting of a negatively charged nitrogen-vacancy NV- center and a nearby 13C nuclear spin. The energy levels, rule selection and radiative transitions are obtained by a new method. The base of this method is the use of a complete set of commuting operators and entangled spin states. An estimation of the carbon hyperfine splitting parameters in the diamond NV- center from side-resonance frequencies is obtained in the frame of this method.

2

EPR spectroscopy of Cu2+ and Mn2+ in borate glasses

Drzewiecki A., Padlyak B., Adamiv V., Burak Y., Teslyuk I.

Nukleonika

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2013

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Vol. 58, No. 3

379--385

EN

Electron paramagnetic resonance (EPR) spectra of the CaB4O7 and LiCaBO3 glasses containing 0.5 and 1.0 mol.% CuO and MnO2 impurity compounds were investigated at room temperature. The glasses with CaB4O7:Cu, LiCaBO3:Cu, CaB4O7:Mn and LiCaBO3:Mn compositions were produced from the corresponding polycrystalline compounds using standard glass synthesis and technological conditions developed by the authors. The EPR spectral parameters of the Cu2+ and Mn2+ centres in both glasses containing 0.5 and 1.0 mol.% CuO and MnO2 doping oxides were determined. Analysis of EPR spectral parameters shows that Cu impurity is incorporated into the CaB4O7 and LiCaBO3 glass network as isolated Cu2+ (3d9, 2D5/2) paramagnetic ions. The Cu2+ ions occupy Ca(Li) sites of the borate glass network coordinated by six O2− anions with geometry of elongated octahedron (D4h symmetry) due to the Jahn- -Teller effect. The EPR spectra of the Mn-doped CaB4O7 and LiCaBO3 glasses are virtually identical and typical of all oxide glasses activated with Mn2+ (3d5, 6S5/2) ions. Observed EPR spectra in the Mn-doped glasses were attributed to isolated Mn2+ (1) centres (geff ≅ 4.3) in octahedral Ca(Li) sites with a strong (fully) rhombic distortion, isolated Mn2+ (2) centres (geff ≅ 2.0) in octahedral Ca(Li) sites with nearly cubic local symmetry as well as pairs and small clusters of the Mn2+ ions, coupled by magnetic dipolar and exchange interactions. On the basis of the obtained results and analysis of referenced data, the local structure of the Cu2+ and Mn2+ centres in the borate glasses have been proposed.

3

The E2 admixture in mixed multipole line 647.6 nm in the spectrum of Bi I

Werbowy S, Kwela J

Optica Applicata

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2006

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Vol. 36, nr 4

s. 535--541

EN

A study of the hyperfine structure of mixed multipole line 646.7 nm of Bi I is reported. A special computer program was designed to obtain the predicted contour of the hyperfine structure of the line for different values of the electric-quadrupole admixture. By variation of free parameters, describing the line shape and the electric-quadrupole admixture D, defined as the ratio of the magnetic-dipole and electric-quadrupole decay rates D = AE2/(AM1 + AE2), the calculated profiles were fitted into the recorded spectra. The D value of the best fit found is (17.8 ± 1.0)%. Our result is compared with recent theories and other experiments.

4

Hyperfine structure and isotope shifts in 461.9 nm forbidden line of Pb I

Wasowicz T J, Drozdowski R, Kwela J

Optica Applicata

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2006

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Vol. 36, nr 4

s. 529--533

EN

Studies of the hyperfine structure and the isotope shifts in the 461.9 nm (1S0–3P1) magnetic-dipole line of Pb I are presented. As a light source the electrodeless discharge tube was used. The high resolution spectral apparatus consisted of a silver coated Fabry–Perot etalon and a grating spectrograph combined with a CCD camera used as a detector. In the analysis of the spectra a computer simulation technique was used. The experiments with the isotope 207Pb yielded the hyperfine structure splitting constant A for the 3P1 level of the 6s26p2 ground configuration. In the experiment with natural lead the isotope shifts between four stable isotopes (204, 206, 207, 208) were measured.