Energy levels of ground and singly excited states of two-electron atoms in dense quantum plasmas

Energy levels of 249 excited levels in nickel-like erbium are calculated using the 3s23p63d10 as a ground state and the single electron excited states from n = 3 to n = 4, 5 orbitals, calculations have been performed using FAC code (Gu. Astrophys. J. 582, 1241 (2003). doi:10.1086/344745 ). The populations are calculated over electron densities from 1020 to 1023 cm−3 and electron temperatures 1/2, 3/4 of the ionization potential of Ni-like Er. The gain coefficients of the transitions are calculated.

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Study of Atomic Populations, Electromagnetically Induced Transparency, and Dispersive Signals in a λ-Type System Under Various Decoherence Effects

Ukrainian Journal of Physics ◽

10.15407/ujpe64.3.197 ◽

2019 ◽

Vol 64 (3) ◽

pp. 197

Author(s):

R. Hazra ◽

Md.M. Hossain

Keyword(s):

Excited States ◽

Electromagnetically Induced Transparency ◽

Energy Levels ◽

Type System ◽

Field Approximation ◽

Peak Height ◽

Probe Field ◽

Set Up ◽

Induced Transparency ◽

Atomic Populations

We have theoretically studied the atomic populations, electromagnetically induced transparency (EIT), and dispersion in a three-level Λ-type system. The density matrix equations are set up with regard for the relaxation of populations of the ground states, and the optical Bloch equations are solved analytically in the weak probe field approximation. Decoherence effects in the ground and excited states on the EIT line shape and dispersive signals are studied, and it is found that the EIT line width increases and the peak height decreases, as the decoherence rates increase in the ground and excited states. On the other hand, we have observed that the dispersive signals are steeper and of high contrast for the lower decoherence rates in the ground and excited states. We have also analyzed the variations of atomic populations of the energy levels at the pump Rabi frequency, as well as the decoherence rate in the ground state.

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Evaluation of Luminescence Decay Measurements Probed on Pure and Doped Pt(IV) Hexahalogeno Complexes. II. Molecular Properties Obtained from Temperature Dependent Lifetime Curves

Zeitschrift für Naturforschung A ◽

10.1515/zna-1997-0513 ◽

1997 ◽

Vol 52 (5) ◽

pp. 447-456

Author(s):

Ingo Biertümpel ◽

Hans-Herbert Schmidtke

Keyword(s):

Excited States ◽

Ground State ◽

Energy Levels ◽

Decay Rates ◽

Rate Equations ◽

Temperature Dependent ◽

Lifetime Measurements ◽

Thermally Activated ◽

Ground State Energies ◽

Higher Excited States

Abstract Lifetime measurements down to nearly liquid helium temperatures are used for determining energy levels and transition rates between excited levels and relaxations into the ground state. Energies are obtained from temperature dependent lifetimes by fitting experimental curves to model functions pertinent for thermally activated processes. Rates are calculated from solutions of rate equations. Similar parameters for pure and doped Pt(IV) hexahalogeno complexes indicate that excited levels largely belong to molecular units. Some of the rates between excited states are only somewhat larger than decay rates into the ground state, which is a consequence of the polyexponential decay measured also at low temperature (2 K). In the series of halogen complexes, the rates between spinorbit levels resulting from 3T1g increase from fluorine to bromine, although energy splittings become larger. Due to the decreasing population of higher excited states in this series, K^PtFö shows a tri-exponential, K2PtCl6 a bi-exponential and FoPtBr6 a mono-exponential decay. In the latter case the population density of higher excited states relaxes so fast that emission occurs primarily from the lowest excited Γ3(3T1g) level. Phase transitions and emission from chromophores on different sites can also be observed.

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Ultrabroadband two-dimensional electronic spectroscopy reveals energy flow pathways in LHCII across the visible spectrum

EPJ Web of Conferences ◽

10.1051/epjconf/201920509034 ◽

2019 ◽

Vol 205 ◽

pp. 09034

Author(s):

Minjung Son ◽

Alberta Pinnola ◽

Roberto Bassi ◽

Gabriela S. Schlau-Cohen

Keyword(s):

Energy Transfer ◽

Excited States ◽

Energy Flow ◽

Energy Levels ◽

Electronic Spectroscopy ◽

Visible Region ◽

Visible Spectrum ◽

Energy Relaxation ◽

Two Dimensional ◽

Flow Pathways

We utilise ultrabroadband two-dimensional electronic spectroscopy to map out pathways of energy flow in LHCII across the entire visible region. In addition to the well-established, low-lying chlorophyll Qy bands, our results reveal additional pathways of energy relaxation on the higher-lying excited states involving the S2 energy levels of carotenoids, including ultrafast carotenoid-to-chlorophyll energy transfer on 90-150 fs timescales.

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Calculs et observations de nouvelles transitions dans le B IV doublement excité

Canadian Journal of Physics ◽

10.1139/p78-045 ◽

1978 ◽

Vol 56 (3) ◽

pp. 358-363 ◽

Cited By ~ 1

Author(s):

K. X. To ◽

R. Drouin

Keyword(s):

Excited States ◽

Energy Levels ◽

Emission Spectra ◽

Doubly Excited States ◽

Doubly Excited ◽

Beam Foil

Energy levels of some doubly-excited states are computed using the atomic screening theory. Using these calculations, eight new transitions are identified in the beam-foil emission spectra of helium-like boron. Agreement between predicted wavelengths and those observed is good. Calculated results are included for further applications.

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