Optical Manipulation of Spin States in Ultracold Magnetic Atoms via an Inner-Shell Hz Transition

TL;DR

This paper introduces an all-optical technique to precisely control and manipulate the spin states of ultracold erbium atoms using a telecom-band transition, enabling advanced quantum simulations.

Contribution

The work demonstrates a novel optical method for deterministic spin control in erbium gases, including spin-state preparation and suppression of spin-exchange collisions.

Findings

Achieved rapid spin-state preparation within tens of microseconds.

Implemented spin-selective light shifts to suppress spin-exchange collisions.

Enabled new possibilities for quantum simulation with controlled spin models.

Abstract

Lanthanides, like erbium and dysprosium, have emerged as powerful platforms for quantum-gas research due to their diverse properties, including a significant large spin manifold in their absolute ground state. However, effectively exploiting the spin richness necessitates precise manipulation of spin populations, a challenge yet to be fully addressed in this class of atomic species. In this work, we present an all-optical method for deterministically controlling the spin composition of a dipolar bosonic erbium gas, based on a clock-like transition in the telecom window at 1299 nm. The atoms can be prepared in just a few tens of microseconds in any spin-state composition using a sequence of Rabi-pulse pairs, selectively coupling Zeeman sublevels of the ground state with those of the long-lived clock-like state. Finally, we demonstrate that this transition can also be used to create spin-selective light shifts, thus fully suppressing spin-exchange collisions. These experimental results unlock exciting possibilities for implementing advanced spin models in isolated, clean and fully controllable lattice systems.