Size quantization of electronic states in very thin platinum films

Oscillatory behaviour of the transport properties in PbTe quantum wells

“…In general, the number of studies on the effect of the thickness of thin films or QWs on the charge carrier concentration and the galvanomagnetic properties is very limited. According to a number of theoretical works, the electron density in metallic [11,16,20,43] and semimetallic [8] thin films increases with increasing d, with a superimposed weak variation (no more than ∼5%), and reaches saturation. The periodicity of this variation is λ F /2.…”

“…Metallic films are not very convenient objects for studying QSEs through transport property measurements because their Fermi wavelength λ F and the oscillation period are comparable to interatomic distances, which requires growing very thin films with a high degree of structural perfection and consequently makes observation of the oscillations more difficult. Nevertheless, experimental work has appeared relatively recently on QSEs in thin metallic films, in which advanced techniques are used for detecting oscillations in the transport properties [10][11][12][13][14][15].…”

Comments on some experimental measures of the non–metal to metal transition in thin films

“…Furthermore, it is also very difficult to connect wires or probes to a monolayer film; almost any current applied will destroy percolation. Metallic and semiconducting thin films, submonolayer to multilayers thick, have recently been characterized on insulating Si(111) (Schad et al 1992;Luo et al 1994;Jalochowski & Bauer 1988;Hasegawa & Ino 1992;Rubenstein et al 1988;Fischer et al 1980;Kimberlin & Tringides 1995), but the most recent studies suggest that these four point probe measurments are dominated by the silicon depletion layer or subsurface region of the substrate and not the overlayer (Kimberlin & Tringides 1995). For systems where the non-metal to metal transition is temperature dependent, the coefficient of the conductivity may be also 'swamped' by the change in metallicity or a change in density independent of metallicity.…”

Derivation of the density of states and distribution functions for two-level systems in glasses

“…While inelastic electron tunneling spectroscopy (IETS) is most famous as a surface vibrational spectroscopy,1-4 there have been a steadily increasing number of papers concerned with the observation of inelastic features in the region above 4000 cm-1 (500 mV). [5][6][7][8][9][10][11] The two best known sources of structure in this region of the tunneling spectrum are electronic transitions of adsorbed species5 and quantum size effect (QSE) structure. [6][7][8][9][10] The theory and experimental information concerning QSE indicate that thin (<100 nm), very smooth, very pure metals must be used.…”

“…[5][6][7][8][9][10][11] The two best known sources of structure in this region of the tunneling spectrum are electronic transitions of adsorbed species5 and quantum size effect (QSE) structure. [6][7][8][9][10] The theory and experimental information concerning QSE indicate that thin (<100 nm), very smooth, very pure metals must be used. In the case of Pb, the deposition must occur below about 150 K with subsequent thermal annealing of the film.…”