Molecular beam electric resonance study of the ground and excited states of cyanoacetylene

1985 ◽  
Vol 82 (4) ◽  
pp. 1702-1704 ◽  
Author(s):  
Robert L. DeLeon ◽  
J. S. Muenter
Keyword(s):  
Excited States ◽  
Molecular Beam ◽  
Electric Resonance

scholarly journals Influence of TOPO and TOPO-CdSe/ZnS Quantum Dots on Luminescence Photodynamics of InP/InAsP/InPHeterostructure Nanowires

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 640
Author(s):  
Artem I. Khrebtov ◽  
Vladimir V. Danilov ◽  
Anastasia S. Kulagina ◽  
Rodion R. Reznik ◽  
Ivan D. Skurlov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Molecular Beam ◽  
Surface Passivation ◽  
Low Energy ◽  
Trioctylphosphine Oxide ◽  
Reverse Transfer ◽  
Semiconductor Heterostructure ◽  
Ligand Type

The passivation influence by ligands coverage with trioctylphosphine oxide (TOPO) and TOPO including colloidal CdSe/ZnS quantum dots (QDs) on optical properties of the semiconductor heterostructure, namely an array of InP nanowires (NWs) with InAsP nanoinsertion grown by Au-assisted molecular beam epitaxy on Si (111) substrates, was investigated. A significant dependence of the photoluminescence (PL) dynamics of the InAsP insertions on the ligand type was shown, which was associated with the changes in the excitation translation channels in the heterostructure. This change was caused by a different interaction of the ligand shells with the surface of InP NWs, which led to the formation of different interfacial low-energy states at the NW-ligand boundary, such as surface-localized antibonding orbitals and hybridized states that were energetically close to the radiating state and participate in the transfer of excitation. It was shown that the quenching of excited states associated with the capture of excitation to interfacial low-energy traps was compensated by the increasing role of the “reverse transfer” mechanism. As a result, the effectiveness of TOPO-CdSe/ZnS QDs as a novel surface passivation coating was demonstrated.

scholarly journals Photochemical R2PI study of chirality and intermolecular forces in supersonic beam

2001 ◽  
Vol 3 (4) ◽  
pp. 223-227 ◽  
Author(s):  
A. Giardini Guidoni ◽  
S. Piccirillo ◽  
D. Scuderi ◽  
M. Satta ◽  
T. M. Di Palma ◽  
...  
Keyword(s):  
Excited States ◽  
Molecular Beam ◽  
Intermolecular Forces ◽  
Excitation Spectra ◽  
Supersonic Molecular Beam ◽  
Spectral Shifts ◽  
Band Origin ◽  
Solvent Molecules ◽  
The One ◽  
Diastereomeric Complexes

One and two-color, mass selected R2PI spectra of theS1←S0transitions in the bare(+)-(R)- 1-phenyl-1-ethanol(ER) and its complexes with different solvent molecules (solv) (-)-(R)-2-butanol(BR) or(+)-(S)-2-butanol(BS), (—)-(R)-2-pentanol (TR) or(+)-(S)-2-pentanol(TS) and(-)-(R)-2-butylamine(AR) or(+)-(S)-2-butylamine(AS), have been recorded after a supersonic molecular beam expansion. The one-color R2PI excitation spectra of the diastereomeric complexes are characterized by significant shifts of their band origin relative to that of bareER. The extent and the direction of these spectral shifts are found to depend upon the structure and the configuration ofsolvand are attributed to different short-range interactions in the ground and excited states of the complexes. In analogy with other diastereomeric complexes, the phenomenological binding energy of the homochiral cluster is found to be greater than that of the heterochiral one. Preliminary measurements of excitation spectrum of(+)-(R)-1-Indanol(IR) is also reported.

Anomalous transitions in two-level systems driven by the ac Stark effect

2001 ◽  
Vol 79 (2-3) ◽  
pp. 533-545 ◽  
Author(s):  
W L Meerts ◽  
I Ozier ◽  
J T Hougen
Keyword(s):  
Molecular Beam ◽  
Stark Effect ◽  
Electric Resonance ◽  
Avoided Crossing ◽  
Different Types ◽  
Two Level Systems ◽  
Experimental Findings ◽  
Ac Stark Effect ◽  
Unusual Type ◽  
Good Agreement

An unusual type of nonresonant absorption signal produced by the ac Stark effect has been observed in a two-level avoided-crossing system. The theory for these anomalous transitions has been developed. The nonresonant signals have been shown to be caused by the perturbation by the oscillating field of the dephasing of the two-level system at the avoided crossing. A series of measurements of these anomalous transitions has been carried out using the avoided-crossing molecular-beam electric-resonance technique. In addition, different types of resonant multiphoton transitions have been investigated. Results are reported for the AE-barrier anticrossing with J = 1 in CH3SiH3. The experimental findings are in good agreement with the theory developed. PACS Nos.: 33.20Bx, 33.80Be, 42.50Hz

Comparison of the Optical Properties of Er3+ Doped Gallium Nitride Prepared by Metalorganic Molecular Beam Epitaxy (MOMBE) and Solid Source Molecular Beam Epitaxy (SSMBE)

1999 ◽  
Vol 595 ◽  
Author(s):  
U. Hömmerich ◽  
J. T. Seo ◽  
J. D. MacKenzie ◽  
C. R. Abernathy ◽  
R. Birkhahn ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Excited States ◽  
Room Temperature ◽  
Molecular Beam ◽  
Average Lifetime ◽  
Green Luminescence ◽  
Si Substrates ◽  
Lifetime Analysis ◽  
Metalorganic Molecular Beam Epitaxy ◽  
Er Doped

AbstractWe report on the luminescence properties of Er doped GaN grown prepared by metalorganic molecular beam epitaxy (MOMBE) and solid-source molecular beam epitaxy (SSMBE) on Si substrates. Both types of samples emitted characteristic 1.54 µm PL resulting from the intra-4f Er3+ transition 4I13/2→4I15/2. Under below-gap excitation the samples exhibited very similar 1.54 µm PL intensities. On the contrary, under above-gap excitation GaN: Er (SSMBE) showed ∼80 times more intense 1.54 µm PL than GaN: Er (MOMBE). In addition, GaN: Er (SSMBE) also emitted intense green luminescence at 537 nm and 558 nm, which was not observed from GaN: Er (MOMBE). The average lifetime of the green PL was determined to be 10.8 µs at 15 K and 5.5 µs at room temperature. A preliminary lifetime analysis suggests that the decrease in lifetime is mainly due to the strong thermalization between the 2H11/2 and 4S3/2 excited states. Nonradiative decay processes are expected to only weakly affect the green luminescence.

Hyperfine Structure of 7Li79,81Br by Molecular‐Beam Electric Resonance

1972 ◽  
Vol 56 (2) ◽  
pp. 855-861 ◽  
Author(s):  
R. C. Hilborn ◽  
T. F. Gallagher ◽  
N. F. Ramsey
Keyword(s):  
Hyperfine Structure ◽  
Molecular Beam ◽  
Electric Resonance
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