78 research outputs found
Automatic grid construction for few-body quantum mechanical calculations
An algorithm for generating optimal nonuniform grids for solving the two-body
Schr\"odinger equation is developed and implemented. The shape of the grid is
optimized to accurately reproduce the low-energy part of the spectrum of the
Schr\"odinger operator. Grids constructed this way are applicable to more
complex few-body systems where the number of grid points is a critical
limitation to numerical accuracy. The utility of the grid generation for
improving few-body calculations is illustrated through an application to bound
states of He trimers
Universal resonant ultracold molecular scattering
The elastic scattering amplitudes of indistinguishable, bosonic,
strongly-polar molecules possess universal properties at the coldest
temperatures due to wave propagation in the long-range dipole-dipole field.
Universal scattering cross sections and anisotropic threshold angular
distributions, independent of molecular species, result from careful tuning of
the dipole moment with an applied electric field. Three distinct families of
threshold resonances also occur for specific field strengths, and can be both
qualitatively and quantitatively predicted using elementary adiabatic and
semi-classical techniques. The temperatures and densities of heteronuclear
molecular gases required to observe these univeral characteristics are
predicted. PACS numbers: 34.50.Cx, 31.15.ap, 33.15.-e, 34.20.-bComment: 4 pages, 5 figure
Effective Range Corrections in Few-Body Systems with large Scattering Length
The effective field theory with contact interactions alone is a powerful tool
to compute low-energy observables for three-body systems with large scattering
length. Recent calculations including effective range corrections are discussed
and results are presented.Comment: 5 pages, 2 figures, talk given at the 18th International IUPAP
Conference on Few-Body Problems in Physics, August 21-26 2006, Santos, Sao
Paulo, Brazi
Ultracold scattering processes in three-atomic helium systems
We review results on scattering observables for He--He and
He--He collisions. We also study the effect of varying the coupling
constant of the atom-atom interaction on the scattering length
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