Spin-exchange collisions of submerged shell atoms below 1 Kelvin

TL;DR

This study investigates whether submerged shell atoms, like Mn, exhibit suppressed spin-exchange collisions at sub-Kelvin temperatures, finding that their collision rates are comparable to non-submerged shell atoms.

Contribution

First experimental measurement of spin-exchange collisions in submerged shell atoms at ultra-low temperatures, challenging assumptions about collision suppression.

Findings

Spin-exchange rates in Mn are similar to Na and H.

Submerged shell configuration does not suppress spin-exchange collisions.

Results suggest similar collisional behavior regardless of shell structure.

Abstract

Angular momentum changing collisions can be suppressed in atoms whose valence electrons are submerged beneath filled shells of higher principle quantum number. To determine whether spin-exchange collisions are suppressed in these "submerged shell" atoms, we measured spin-exchange collisions of six hyperfine states of Mn at temperatures below 1 K. Although the 3d valence electrons in Mn are submerged beneath a filled 4s orbital, we find that the spin exchange rate coefficients are similar to those of Na and H (which are non-submerged shell atoms).