Distinct role of electric field and vector potential in strong-field tunneling ionization

Light can be described either by its field or potential, which are often interchangeable. We theoretically investigate the distinct roles of the electric field and the vector potential of an ultrashort laser pulse in strong-field tunneling ionization, based on their distinct central frequencies. Employing the conservation law between the angular momentum and energy, we demonstrate that quantum tunneling dynamics is driven by the electric field, while the subsequent classical motion in the continuum is governed by the vector potential. Our work casts new light on the fundamental laser-matter interactions and offers a fresh perspective on the application of ultrashort laser pulses in strong-field physics.