0000000000144037
AUTHOR
I. Yu. Protsenko
Matching emission centers of electrons and photons in current-carrying silver nanoparticle films
Current flow through a nanoparticle film (two-dimensional ensemble of small tunnel-coupled metal particles on a dielectric substrate) is accompanied by electron and photon emission. It has a localized character (originates from emission centers). With an increase in applied voltage, the number of emission centers increases, and with further increase, some of them may burn out. In dark conditions, photon emission centers are visible with a bare eye. To visualize electron emission centers, emission electron microscopy is used. The conducted measurements allow comparison of the number and relative positions of electron and photon emission centers. It is shown that electrons and photons are emi…
Characterization and magnetic properties of nanoparticles based on FePt solid solution with an oxide shell
Abstract We present the results of magnetic properties investigations of ferromagnetic nanoparticles which ensembled with ferromagnetic shell. The aim of this work is to study the connection of structure–phase composition and thermal treatment with the magnetic properties, partially, with the coercive force and the exchange bias field in a two-dimension spin system of core–shell type. It is found that the exchange bias field increases with the growth of the oxide shell thickness. This is realized by annealing in a dosed oxygen flow. The decrease of the coercive force with the increase of annealing temperature is connected with the concentration effect (the concentration of ferromagnetic par…
Spectral Measurement of Photon Emission from Individual Gold Nanoparticles Using Scanning Tunneling Microscopy
The light emission spectra of individual Au nanoparticles induced by a scanning tunneling microscope (STM) have been investigated. Two-dimensional ensembles of tunnel-coupled Au particles were prepared by thermal evaporation onto a native oxide silicon wafer in ultrahigh vacuum (10 – 9 mbar). Our STM measurements show a single peak at photon energy 1.6 eV in the tunneling mode and two peaks at 2.2 eV (connected with the Mie plasmon) and 1.45 eV (a new peak which was not discussed in literature before) in the field emission mode.
Investigation of a Ge nanoparticle film by means of electron stimulated photon emission spectroscopy
Abstract Electron stimulated photon emission spectroscopy was used for the study of the electronic structure of Ge nanoparticles. A nanoparticle film was prepared by thermal deposition on a quartz substrate. Photon emission was stimulated by electron bombardment at energies of several hundred electron volts. Electron field emission from a W-tip was used at tip voltage U t = 100–600 eV. A spectrometer in combination with a liquid nitrogen cooled charge-coupled device (CCD) camera was used for light detection. Light emission spectra were measured in the energy range 1.18–4.2 eV. They are characterized by features at ∼1.6 and ∼3.1 eV. A comparison with light emission spectra obtained with ano…