Singularities of Floquet Scattering and Tunneling
arXiv:1708.09828 · doi:10.1103/PhysRevA.97.042705
Abstract
We study quasi-bound states and scattering with short range potentials in three dimensions, subject to an axial periodic driving. We find that poles of the scattering S-matrix can cross the real energy axis as a function of the drive amplitude, making the S-matrix nonanalytic at a singular point. For the corresponding quasi-bound states that can tunnel out of (or get captured within) a potential well, this results in a discontinuous jump in both the angular momentum and energy of emitted (absorbed) waves. We also analyze elastic and inelastic scattering of slow particles in the time dependent potential. For a drive amplitude at the singular point, there is a total absorption of incoming low energy (s-wave) particles and their conversion to high energy outgoing (mostly p-) waves. We examine the relation of such Floquet singularities, lacking in an effective time independent approximation, with well known "spectral singularities" (or "exceptional points"). These results are based on an analytic approach for obtaining eigensolutions of time-dependent periodic Hamiltonians with mixed cylindrical and spherical symmetry, and apply broadly to particles interacting via power law forces and subject to periodic fields, e.g. co-trapped ions and atoms.
22 pages, 15 figures, this article supersedes arXiv:1506.08779
References in corpus (20)
- The physics of exceptional points
- Coherent Perfect Absorbers: Time-reversed Lasers
- PT-symmetry breaking and laser-absorber modes in optical scattering systems
- Periodically-driven quantum systems: Effective Hamiltonians and engineered gauge fields
- A trapped single ion inside a Bose-Einstein condensate
- Experimental realization of Floquet PT-symmetric systems
- Quantum theory of ultracold atom-ion collisions
- Time independent description of rapidly oscillating potentials
- Universal properties in ultracold ion-atom interactions
- Unraveling the Structure of Ultracold Mesoscopic Molecular Ions
- Ground state properties of ultracold trapped bosons with an immersed ionic impurity
- Micromotion in trapped atom-ion systems
- Asymptotic Bound-state Model for Feshbach Resonances
- Trapped ions in Rydberg-dressed atomic gases
- A Primer on Resonances in Quantum Mechanics
- Multiscale quantum-defect theory for two interacting atoms in a symmetric harmonic trap
- AC-Stark shift and photoionization of Rydberg atoms in an optical dipole trap
- Bose atoms in a trap: a variational Monte Carlo formulation for the universal behavior at the Van der Waals length scale
- Two- and three-body problem with Floquet-driven zero-range interactions
- Oscillating potential well in complex plane and the adiabatic theorem