Spectroscopic Evidence Of Discrete Energy Levels In Nanosize Clusters Of Metal Atoms Using A Low Temperature STM

2006 ◽  
Author(s):  
L. L. A. Adams ◽  
B. W. Lang ◽  
A. M. Goldman
Keyword(s):  
Low Temperature ◽  
Energy Levels ◽  
Discrete Energy ◽  
Spectroscopic Evidence ◽  
Metal Atoms

scholarly journals Structural Evolution of Carbon Dots During Low Temperature Pyrolysis

Nanoscale ◽  
2022 ◽  
Author(s):  
Hui Luo ◽  
Leonardo Lari ◽  
Hyunjeong Kim ◽  
Servann Herou ◽  
Liviu Cristian Tanase ◽  
...  
Keyword(s):  
Optical Properties ◽  
Low Temperature ◽  
Carbon Dots ◽  
Energy Levels ◽  
Structural Evolution ◽  
Electronic States ◽  
Discrete Energy ◽  
Low Temperature Pyrolysis

Carbon dots (CDs) are an emerging class of photoluminescent material. Their unique optical properties arise from the discrete energy levels in their electronic states, which directly relate to their crystalline...

Low-Temperature Diffusion of Transition Metals at the Presence of Radiation Defects in Silicon

2011 ◽  
Vol 178-179 ◽  
pp. 421-426
Author(s):  
Jan Vobecký ◽  
Volodymyr Komarnitskyy ◽  
Vít Záhlava ◽  
Pavel Hazdra
Keyword(s):  
Low Temperature ◽  
Active Sites ◽  
Carrier Lifetime ◽  
High Energy ◽  
Deep Levels ◽  
Radiation Defects ◽  
Metal Atoms ◽  
Temperature Diffusion ◽  
Concentration Enhancement ◽  
Application Potential

Low-temperature diffusion of Cr, Mo, Ni, Pd, Pt, and V in silicon diodes is compared in the range 450 - 800 oC. Before the diffusion, the diodes were implanted with high-energy He2+ to assess, if the radiation defects enhance the concentration of metal atoms at electrically active sites and what is the application potential for carrier lifetime control. The devices were characterized using AES, XPS, DLTS, OCVD carrier lifetime and diode electrical parameters. The metal atoms are divided into two groups. The Pt, Pd and V form deep levels in increased extent at the presence of radiation defects above 600 oC, which reduces the excess carrier lifetime. It is shown as a special case that the co-diffusion of Ni and V from a NiV surface layer results fully in the concentration enhancement of the V atoms. The enhancement of the acceptor level V-/0 (EC 0.203 eV) and donor level V0/+ (EC 0.442 eV) resembles the behavior of substitutional Pts. The second group is represented by the Mo and Cr. They easily form oxides, which can make their diffusion into a bulk more difficult or impossible. Only a slight enhancement of the Cr-related deep levels by the radiation defects has been found above 700 oC.

scholarly journals Theoretical Bounds on Electron Energy Filtering in Disordered Nanomaterials

2019 ◽  
Author(s):  
Amro Dodin ◽  
Brian F. Aull ◽  
Roderick R. Kunz ◽  
Adam Willard
Keyword(s):  
Theoretical Model ◽  
Electron Energy ◽  
Energy Levels ◽  
Additional Source ◽  
Discrete Energy ◽  
Energy Filtering ◽  
Simple Theoretical Model ◽  
Particle Polydispersity ◽  
Electron Energy Filtering ◽  
Individual Nanoparticles

This manuscript presents a theoretical model for determining the electron energy filtering properties of nanocomposite materials. Individual nanoparticles can serve as energy filters for tunneling electrons due their discretized energy levels. Nanomaterials comprised of many individual nanoparticles can in principle serve the same purpose, however, particle polydispersity can lead to an additional source of energetic broadening. We describe a simple theoretical model that includes the effects of discrete energy levels and inhomogeneous broadening. We use this model to identify the material parameters needed for effective energy filtering by quantum dot solids.

Small is different

2021 ◽  
pp. 81-93
Author(s):  
Adrian P Sutton
Keyword(s):  
Crystal Structure ◽  
Electronic Structure ◽  
Catalytic Activity ◽  
Giant Magnetoresistance ◽  
Energy Levels ◽  
Exclusion Principle ◽  
Thermodynamic Quantities ◽  
Discrete Energy ◽  
Size Dependent ◽  
The World

As the size of a material decreases to the nanoscale its properties become size-dependent. This is the world of nanoscience and nanotechnology. At the nanoscale the crystal structure may change and thermodynamic quantities such as the melting point also change. Changes in the catalytic activity and colour of nanoparticles suspended in a liquid indicate changes to the electronic structure. Quantum dots have discrete energy levels that can be modelled with the particle-in-a-box model. Excitons may be created in them using optical illumination, and their decay leads to fluorescence with distinct colours. The classical and quantum origins of magnetism are discussed. The origin of magnetoresistance in a ferromagnet is described and related to the exclusion principle. The origin of the giant magnetoresistance effect and its exploitation in nanotechnology is outlined.

scholarly journals Discrete spectrum of many body Schrödinger operators with non-constant magnetic fields II

1997 ◽  
Vol 145 ◽  
pp. 69-98
Author(s):  
Tetsuya Hattori
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Discrete Spectrum ◽  
Bound States ◽  
Atomic System ◽  
Energy Levels ◽  
Schrödinger Operators ◽  
Schrodinger Operators ◽  
Many Body ◽  
Discrete Energy

This paper is continuation from [10], in which we studied the discrete spectrum of atomic Hamiltonians with non-constant magnetic fields and, more precisely, we showed that any atomic system has only finitely many bound states, corresponding to the discrete energy levels, in a suitable magnetic field. In this paper we show another phenomenon in non-constant magnetic fields that any atomic system has infinitely many bound states in a suitable magnetic field.

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