2025 CAP Congress / Congrès de l'ACP 2025

Session

(DAMOPC) T3-3 Rydberg Atoms and Radiative Transfer | Atomes de Rydberg et transferts radiatifs (DPAMPC)

T3-3

10 Jun 2025, 16:15

Conveners

(DAMOPC) T3-3 Rydberg Atoms and Radiative Transfer | Atomes de Rydberg et transferts radiatifs (DPAMPC)

• Jens Lassen

249. High precision theory for the Rydberg states of helium up to n = 30: a critical test of QED

Gordon Drake (University of Windsor)

10/06/2025, 16:15

Atomic, Molecular and Optical Physics, Canada / Physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC)

Oral (Non-Student) / Orale (non-étudiant(e))

Recent measurements for the ionization energies of the Rydberg singlet-P and triplet-P states of helium for principal quantum number $n = 24$ to 100 [1] present a new challenge to high-precision atomic theory. A long-standing obstacle is that the accuracy of variational calculations for two-electron systems rapidly declines with increasing $n$. The problem has now become urgent with the...

77. Superradiance and Subradiance in Astrophysics: Rethinking Light-Matter Interactions

Dr Fereshteh Rajabi (McMaster University)

10/06/2025, 16:45

Atomic, Molecular and Optical Physics, Canada / Physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC)

Invited Speaker / Conférencier(ère) invité(e)

Astrophysical radiative transfer models typically assume that atoms and molecules emit and absorb radiation independently. However, recent evidence suggests that cooperative quantum effects—such as superradiance and potentially subradiance—can significantly alter radiative behavior.

Superradiance, a cooperative quantum emission process, has been observed in star-forming regions, where it...

290. Tunable domain-wall dynamics in multi-domain spin structures in an ultracold 87Rb gas

Olha Farion (Simon Fraser University)

10/06/2025, 17:15

Atomic, Molecular and Optical Physics, Canada / Physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC)

Oral Competition (Graduate Student) / Compétition orale (Étudiant(e) du 2e ou 3e cycle)

We study domain wall motion in pseudo-spin-½ ultracold $^{87}$Rb gas initialized in an ‘up-down-up’ configuration, with helical domain walls between the regions of different magnetization. The interplay between diffusive pressure and induced spin-currents due to spin-exchange collisions leads to complex domain-wall dynamics. We qualitatively distinguish two regimes of wall motion. At short...