diffusion length

diffusion length

[də′fyü·zhən ‚leŋkth]
(physics)
The average distance traveled by a particle, such as a minority carrier in a semiconductor or a thermal neutron in a nuclear reactor, from the point at which it is formed to the point at which it is absorbed.
References in periodicals archive ?
Further, as the diffusion length of these excitons is only of few nanometres (approximately 8-10 nm) before it will relax back to the ground state so; the heterojunction for excitons splitting should be within the excitons diffusion limit (i.
By tracking down the rapid motion of electrons in the material, they have been able to determine the diffusion length -- how far electrons can travel without getting trapped by imperfections in the material -- as well as mobility -- how fast the electrons can move through the material.
This equation [20, 21], which predicts attainment of steady state, contains a dimensionless parameter, [tau], which represents the squared ratio of the diffusion length to the disk radius:
It is shown that for the characteristic diffusion length scale of the eddies much smaller than the height of the Ekman bottom boundary layer the model results in an analytic expression for the vertical distribution of the concentration of suspended sediment, which includes both cases, with and without the lutocline.
Moreover, there is a correlation between the overlap parameter and the diffusion length.
where L is the electron diffusion length calculated by [square root of (D[tau])] and q is the charge of an electron equal to 1.
D] = characteristic diffusion length (4) [upsilon] = kinematic viscosity (Vogel, 1994) (5) D = molecular diffusion coefficient for a small chemical molecule (Jackson, 1980 (6) T = eddy turnover time (Jimenez, 1997) [delta] = length scale [varepsilon] = energy dissipation rate Comparision of the properties of the biologically created copepod mating trail and and those for the physically derived small-scale turbulent feature, a vortex tube.
1]), the diffusion length ([-square root of D/r]), and the half-saturation density ([F.
Characterization: A number of techniques have been developed for the systematic study of the effect of the nature and density of dopants on properties such as minority carrier diffusion length, conductivity, |4,5~ photoconductivity, |4,8~ majority carrier density and mobility.

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