# Vibrational-ground-state zero-width resonances for laser filtration: An extended semiclassical analysis

## TL;DR

This paper extends a semiclassical model to identify zero-width resonances in Na2 molecules under strong laser fields, enabling ground vibrational state filtering for molecular cooling.

## Contribution

It introduces an extended semiclassical analysis for zero-width resonances at c_minus-type crossings, facilitating ground state laser filtration strategies.

## Key findings

- Identification of critical wavelength and intensity pairs for ground state ZWRs.
- Demonstration of ZWR morphology in laser parameter space.
- Potential application in molecular cooling to ground vibrational state.

## Abstract

A semiclassical model supporting the destructive interference interpretation of zero-width resonances (ZWR) is extended to wavelengths inducing c_minus-type curve crossing situations in Na2 strong field dissociation. This opens the possibility to get critical couples of wavelengths lambda and field intensities I to reach ZWRs associated with the ground vibrationless level v = 0, that, contrary to other vibrational states (v > 0), is not attainable for the commonly referred c+-type crossings. The morphology of such ZWRs in the laser (I; lambda) parameter plane and their usefulness in filtration strategies aiming at molecular cooling down to the ground v = 0 state are examined within the frame of an adiabatic transport scheme.