Efficient numerical method for locating Feshbach resonances of ultracold molecules in external fields

摘要: Collision properties of atoms and molecules in low temperature gases can be controlled by applying an external magnetic or electric field. The field shifts the energy levels colliding particles, which gives rise to Feshbach resonances modifying scattering cross sections. occur at particular magnitudes field, where a bound state collision complex is degenerate with state. positions are usually identified computing either sections states as functions magnitude. We propose more efficient method for locating that requires neither these computations. In particular, we show log-derivative total wave function classically allowed region strength. This procedure particularly useful narrow may hard identify other methods.