Energy Spectra of Electrons Backscattered from Sample Surfaces with Heterostructures using Field-Emission Scanning Tunneling Microscopy

Abstract

Possibilities of manipulating the Rabi frequency and luminescence rate from degenerate-level systems as well as the velocity of self-induced transparency of multi-level media are studied using a unitary transformation. The Rabi frequency and luminescence rate of an electronic system whose ground level is degenerate and coupled to a resonant mode are found to depend on the level of the degeneracy. The velocity of multi-mode optical solitons in a multi-level medium is found to be influenced by the number of propagating resonant pulses. Physical realizations of relevant systems are proposed.

Local secondary-electron emission spectra of graphite and gold surfaces obtained using the Scanning Probe Energy Loss Spectrometer (SPELS)

“…The increasing level of control over the properties of materials on the nanometre scale is driving the creation of new types of instruments for nanometrology. One such instrument is the Scanning Probe Energy Loss Spectrometer (SPELS) [1][2][3][4][5][6][7][8][9][10]. Recently Yin et al [11] exploited the SPELS instrument to obtain characteristic SEE peaks from graphite, i.e., in addition to the energy loss features associated with the π and (π + σ ) surface plasmons [1].…”

Fabrication of co-axial field emitter tips for scanning probe energy loss spectroscopy

“…An alternative approach is to collect electrons field emitted by the STM tip, and subsequently backscattered by the surface, in order to obtain information from the electron energy loss spectrum (EELS). The scanning probe energy loss spectrometer (SPELS) is a hybrid instrument, which combines an STM tip with an electron energy analyzer to achieve local EELS measurements [5][6][7][8][9][10][11][12][13][14][15][16][17], with a previously demonstrated resolution of 50 nm, and a theoretically achievable resolution of 10 nm [8]. It detects electrons backscattered from the tip-surface junction when the STM tip is operated in field emission mode.…”

Simulation Study of Auger Electron Emission Features in Tip–Sample Electric Field Region for Scanning Probe Electron Energy Spectrometer

“…The combination of the scanning probe technique and the electron energy spectroscopy technique is a promising way to resolve this problem. Great efforts have been made by several groups, such as Miyatake et al, 9,10) Tomitori et al, [11][12][13][14] Palmer et al, [15][16][17][18][19] and our group. [20][21][22] In these studies, the STM tip is used as a field emission electron source and the elemental identification can be achieved by measuring the energy spectra of the electrons backscattered from the sample surface stimulated by the field emission electrons from the STM tip.…”

“…However, a strong electric field will be introduced between the STM tip and the sample surface, which will severely suppress the emitted electrons from the sample surface and make them difficult to be detected. The work of both Miyatake et al 9,10) and Tomitori et al [11][12][13][14] have approved that an unscreened STM tip is inapplicable for the measurement of the Auger electron energy spectra (AES) as the relative low energy of Auger electrons compared to the biasing voltage applied to the tip-sample. A tip shield is thus necessary for these kinds of experiments.…”