Charged Polarons and Molecules in a Bose-Einstein Condensate

Area of Science:

• Quantum simulation
• Ultracold atomic physics
• Hybrid quantum systems

Background:

• Ultracold hybrid ion-atom gases are emerging platforms for quantum simulation.
• The interaction between ions and ultracold atoms presents unique physics challenges.
• Understanding these interactions is key to advancing quantum control and simulation.

Purpose of the Study:

• To investigate the physics of a mobile ion interacting with a Bose-Einstein condensate.
• To explore the interplay between few- and many-body physics in such systems.
• To characterize the resulting polaronic and molecular states and their spectral properties.

Main Methods:

• Utilizing a variational ansatz to model the system.
• Employing field theory techniques for a comprehensive description.
• Calculating the full spectral response of the ion.

Main Results:

• Observed intricate polaronic and molecular states due to long-range ion-atom interactions.
• Identified a mesoscopic dressing cloud of polarons from thermodynamic arguments.
• Demonstrated that molecular spectral weight scales with density, exceeding short-range pseudopotential descriptions.

Conclusions:

• The study elucidates the rich physics of ion-atom interactions in Bose-Einstein condensates.
• The findings provide a deeper understanding of polaronic and molecular states in hybrid quantum systems.
• The calculated quantum dynamics after a quench experiment offer insights into system evolution.