Searcharxiv⌕ Search

arXiv · 2610.40953

Variational surface matching for multichannel molecular photoionization

Abstract

We present an improved method for computing multichannel scattering states in the \ASTRA{} (AttoSecond TRAnsitions) molecular ionization code. Our pole-free Galerkin method with variational surface matching (PFG-VSM) yields a boundary response that is stationary with respect to errors in the interior wave function. Compared with matching based on directly evaluated radial derivatives, this formulation yields substantially faster convergence and greater numerical stability as the number of open channels increases. Comparison with a numerical solution of the exactly separable $\mathrm H_2^+$ problem establishes the accuracy attainable in a hybrid Gaussian--B-spline basis for a polycentric potential, independently of many-electron close-coupling approximations. A direct comparison of the two matching prescriptions for CO demonstrates the stability of the variational formulation under radial-basis coarsening. For neon, agreement with the NewStock atomic ionization code tests the treatment of the continuum degeneracies that arise when rotational symmetry is represented in $D_{2h}$. The excellent agreement with the independent \XCHEM{} molecular ionization code for CO partial cross sections and molecular-frame photoelectron angular distributions, both away from and across resonances, is a strong confirmation of the correctness of both codes. A comparison for pyrazine extends this validation to a larger polyatomic target.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Carlos Marante, Vicent J Borràs, Jesús González Vázquez, Fernando Martín, Luca Argenti. 2026-10-29. Variational surface matching for multichannel molecular photoionization. https://arxiv.org/abs/2610.40953

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Observation of s-p Coupling in Ultralong-Range Rydberg Molecules

Ultralong-range Rydberg molecules, formed by the interaction between a highly excited Rydberg atom and a ground-state atom, provide a unique platform for exploring quantum phenomena spanning nanometer- to micrometer distances as well as exotic few-body interactions. The molecular binding arises from electron-atom scattering, which is conventionally described by an independent s- and p-wave channels picture. Here we report the experimental observation of s-p coupling in Rb(nS)-Rb(5S) ultralong-range Rydberg molecules via high-resolution photoassociation spectroscopy. By varying the principal quantum number n from 31 to 36, we resolve an avoided crossing between the s- and p-wave molecular states: whenever a vibrational level bound by the p-wave well approaches one bound by the s-wave well in energy, the two states are mixed by the off-diagonal coupling U_sp, and the shifted s-wave level is identified, which is consistent with theoretical predictions. This mixing is most pronounced for low-node p-wave molecules, whose binding energies lie closer to those of the s-wave molecules. The resulting level repulsion and redistribution of spectral intensity reveal the mixed s-p character of ultralong-range Rydberg molecules and provide a more precise molecular spectroscopy.

physics.atom-ph↗

Wavefront engineering with atomic Huygens' surfaces made simple

Atomic arrays provide a cooperative platform for light-mediated interactions in nonlocal metasurfaces which can operate in the quantum regime without nanofabricated optical elements or intrinsic material absorption. We present a minimal atomic implementation to harness wavefront engineering and create a near-ideal intrinsic atomic Huygens' surface. A simple bilayer square lattice with a two-atom unit cell, not limited to small lattice spacings, provides near-unity reflectionless transmission and a full $2π$ phase control of transmitted light without the localized site-dependent level shifts of previous proposals. This simplification is achieved through nonlocal radiative excitations that provide the familiar electric-dipole response with even radiation parity as well as an odd-parity radiation channel whose leading multipolar interpretation combines magnetic-dipole and electric-quadrupole contributions in atoms exhibiting only electric dipole transitions. This eliminates the need to simultaneously excite pure electric-dipole and magnetic-dipole responses with exactly matched radiation. We derive a two-mode model for this response and show that it accurately captures full coupled-dipole simulations near the optimal lattice spacings. Because of the wide applicability of coupled-dipole models, the relevance of our microscopic analysis extends beyond atomic physics to nanostructured metasurfaces. Moreover, the same platform also connects directly to established subradiance-protected single-photon storage protocols, suggesting a route toward combining wavefront engineering, storage, and retrieval in a simple atomic bilayer.

physics.atom-ph↗

Ultracold polar molecules for quantum science and technology

Ultracold polar molecules present a rich platform for experimental quantum science leveraging their unique properties. Of particular relevance is the intrinsic electric dipole moment of the molecule, which results in strong coupling to microwave fields and can be used to engineer long-range, anisotropic, and tunable dipole-dipole interactions. Such interactions can generate entanglement between molecules and enable the study of novel quantum many-body phenomena in parameter regimes inaccessible in other systems. Modern experiments in optical tweezers and optical lattices have demonstrated controlled interactions between molecules in coherent quantum states, and recently bulk gases of molecules have been cooled to quantum degeneracy. Motivated by these landmark advances, we present this article to explain many of the key concepts relevant to current research in the field.

physics.atom-ph↗