11,359 research outputs found
Ionized cluster beam deposition
Ionized Cluster Beam (ICB) deposition, a new technique originated by Takagi of Kyoto University in Japan, offers a number of unique capabilities for thin film metallization as well as for deposition of active semiconductor materials. ICB allows average energy per deposited atom to be controlled and involves impact kinetics which result in high diffusion energies of atoms on the growth surface. To a greater degree than in other techniques, ICB involves quantitative process parameters which can be utilized to strongly control the characteristics of films being deposited. In the ICB deposition process, material to be deposited is vaporized into a vacuum chamber from a confinement crucible at high temperature. Crucible nozzle configuration and operating temperature are such that emerging vapor undergoes supercondensation following adiabatic expansion through the nozzle
Quantum ferromagnetic transition in disordered itinerant electron systems
An effective field theory is derived for the ferromagnetic transition of
diffusive electrons at T=0. The static disorder which leads to diffusive
electron dynamics induces an effective long-range interaction between the spins
of the form 1/r^(2d-2). This leads to unusual scaling behavior at the quantum
critical point, which is determined exactly. The crossover from this quantum
fixed point to the classical Heisenberg fixed point should be observable in
ferromagnetic materials with low Curie temperatures.Comment: 4pp, REVTeX, no figs, final version as publishe
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