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arXiv · 1105.4483

Multichannel Quantum Defect Theory for cold molecular collisions

James F. E. Croft·Alisdair O. G. Wallis·Jeremy M. Hutson·Paul S. Julienne
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Abstract

Multichannel Quantum Defect Theory (MQDT) is shown to be capable of producing quantitatively accurate results for low-energy atom-molecule scattering calculations. With a suitable choice of reference potential and short-range matching distance, it is possible to define a matrix that encapsulates the short-range collision dynamics and is only weakly dependent on energy and magnetic field. Once this has been produced, calculations at additional energies and fields can be performed at a computational cost that is proportional to the number of channels N and not to N^3. MQDT thus provides a promising method for carrying out low-energy molecular scattering calculations on systems where full exploration of the energy- and field-dependence is currently impractical.

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James F. E. Croft, Alisdair O. G. Wallis, Jeremy M. Hutson, Paul S. Julienne. 2011-08-29. Multichannel Quantum Defect Theory for cold molecular collisions. https://doi.org/10.1103/physreva.84.042703

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