scholarly journals Evaluating the Solvent Stark Effect from Temperature‐Dependent Solvatochromic Shifts of Anthracene

ChemPhysChem ◽  
2020 ◽  
Vol 21 (7) ◽  
pp. 610-615
Author(s):  
Timais Janz ◽  
Manuel Güterbock ◽  
Fabian Müller ◽  
Martin Quick ◽  
Ilya N. Ioffe ◽  
...  
Keyword(s):  
Stark Effect ◽  
Temperature Dependent ◽  
Solvatochromic Shifts

Structural and Optical Studies of InGaN/GaN Superlattices Implanted with Eu Ions

MRS Advances ◽  
2017 ◽  
Vol 2 (3) ◽  
pp. 179-187
Author(s):  
Jingzhou Wang ◽  
Venkata R. Thota ◽  
Eric A. Stinaff ◽  
Mohammad Ebdah ◽  
Andre Anders ◽  
...  
Keyword(s):  
Stark Effect ◽  
Annealing Temperature ◽  
Chemical Vapor ◽  
Blue Shift ◽  
Photoluminescence Spectra ◽  
Temperature Dependent ◽  
Optical Studies ◽  
Quantum Confined Stark Effect ◽  
Spectral Shifts ◽  
Before And After

ABSTRACTIn0.06Ga0.94N/GaN superlattices (SLs) grown on sapphire (0001) by metalorganic chemical vapor deposition were studied before and after europium (Eu) ion implantation to understand the strain induced-effects in the SL structure. The implanted SLs were investigated as a function of the thermal annealing temperature up to 1000 °C in nitrogen ambient. Temperature dependent photoluminescence spectra showed a red-shift of the SL emission peaks due the quantum confined Stark effect, followed by a blue-shift due to In atoms out-diffusion from the In0.06Ga0.94N quantum well, for both Eu ions implanted and unimplanted SLs. The amplitude of observed spectral shifts was smaller and the line width of the SLs emission peaks were narrower in the SLs:Eu3+ as compared to the unimplanted SLs. It is concluded that Eu3+ ions modified the strain in the SLs acting like impurity and/or defects getter in implantation degraded SLs resulting in material phase purification and improvements of SLs optical properties.

Recombination Dynamics of InGaN/GaN Multiple Quantum Wells With Different Well Thickness

MRS Advances ◽  
2016 ◽  
Vol 1 (2) ◽  
pp. 197-202 ◽  
Author(s):  
X. C. Wei ◽  
L. Zhang ◽  
N. Zhang ◽  
J. X. Wang ◽  
J. M. Li
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Stark Effect ◽  
Turning Point ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Temperature Dependent ◽  
Quantum Confined Stark Effect ◽  
Exciton Localization ◽  
Recombination Dynamics

ABSTRACTRecombination dynamics of InGaN/GaN multiple quantum wells (MQWs) with different well thickness have been studied. From the behaviour of temperature dependent photoluminescence, we find that the activation energy decreases with the well thickness increasing. In addition, with temperature changing from 10K to room temperature, the “W” shape of full width of half maximum is also thickness related, and it becomes more obvious with the well thickness increasing. These results indicate that the dominant recombination dynamics change from exciton localization to quantum confined stark effect with well thickness increasing. From our measurement, the InGaN/GaN MQWs with 3nm thickness seems a turning point, which shows the best optimized optical and structural properties.

(111) Monocrystalline Nickel Films

1972 ◽  
Vol 30 ◽  
pp. 512-513
Author(s):  
T.E. Pratt ◽  
R.W. Vook
Keyword(s):  
Film Thickness ◽  
Deposition Rate ◽  
Room Temperature ◽  
Narrow Range ◽  
High Vacuum ◽  
Residual Pressure ◽  
Temperature Dependent ◽  
Deposition Parameters ◽  
Transmission Electron ◽  
Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

A TEM study of electron tunneling in biological macromolecules

1987 ◽  
Vol 45 ◽  
pp. 140-141
Author(s):  
J. A. Panitz
Keyword(s):  
Stark Effect ◽  
Electron Tunneling ◽  
Imaging Modality ◽  
Tunneling Current ◽  
Biological Species ◽  
Scanning Tunneling ◽  
Biological Macromolecules ◽  
Flat Surfaces ◽  
Virus Particles ◽  
Stm Images

Tunneling is a ubiquitous phenomenon. Alpha particle disintegration, the Stark effect, superconductivity in thin films, field-emission, and field-ionization are examples of electron tunneling phenomena. In the scanning tunneling microscope (STM) electron tunneling is used as an imaging modality. STM images of flat surfaces show structure at the atomic level. However, STM images of large biological species deposited onto flat surfaces are disappointing. For example, unstained virus particles imaged in the STM do not resemble their TEM counterparts.It is not clear how an STM image of a biological species is formed. Most biological species are large compared to the nominal electrode separation of ∼ 1nm that is required for electron tunneling. To form an image of a biological species, the tunneling electrodes must be separated by a distance that would normally be too large for a tunneling current to be observed.

A. C. Stark effect on the 4713 Å line emitted by a helium glow discharge in the field of a multimode T.E.A. CO2 laser

1982 ◽  
Vol 43 (6) ◽  
pp. 875-881 ◽  
Author(s):  
B. Dubreuil ◽  
P. Pignolet ◽  
A. Catherinot ◽  
P. Davy
Keyword(s):  
Glow Discharge ◽  
Co2 Laser ◽  
Stark Effect

STARK EFFECT IN QUANTUM WELLS : RAMAN SCATTERING BY INTERSUBBAND TRANSITIONS

1987 ◽  
Vol 48 (C5) ◽  
pp. C5-179-C5-182
Author(s):  
K. BAJEMA ◽  
R. MERLIN ◽  
F.-Y. JUANG ◽  
S.-C. HONG ◽  
J. SINGH ◽  
...  
Keyword(s):  
Raman Scattering ◽  
Quantum Wells ◽  
Stark Effect ◽  
Intersubband Transitions
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