Low-energy universality and scaling of van der Waals forces

Journal Article · Thu Apr 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.044701· OSTI ID:21408748

Calle Cordon, A; Ruiz Arriola, E ^[1]

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1. Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)

At long distances, interactions between neutral ground-state atoms can be described by the van der Waals potential. In the ultracold regime, atom-atom scattering is dominated by s-waves phase shifts given by an effective range expansion in terms of the scattering length {alpha}{sub 0} and the effective range r{sub 0}. We show that while the scattering length cannot be predicted for these potentials, the effective range is given by the universal low-energy theorem r{sub 0}=A+B/{alpha}{sub 0}+C/{alpha}{sub 0}{sup 2}, where A, B, and C depend on the dispersion coefficients C{sub n} and the reduced diatom mass. We confront this formula to about 100 determinations of r{sub 0} and {alpha}{sub 0} and show why the result is dominated by the leading dispersion coefficient C{sub 6}. Universality and scaling extend much beyond naive dimensional analysis estimates.

• OSTI ID: 21408748
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 81; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ALGAE
ATOM COLLISIONS
ATOM-ATOM COLLISIONS
ATOMS
CHROMOPHYCOTA
COLLISIONS
DIATOMS
DIMENSIONS
ENERGY LEVELS
GROUND STATES
LENGTH
LOW-ENERGY THEOREM
PARTIAL WAVES
PHASE SHIFT
PLANTS
POTENTIALS
S WAVES
SCALING
SCATTERING LENGTHS
VAN DER WAALS FORCES