Observation of generalized t-J spin dynamics with tunable dipolar interactions.

Area of Science:

• Quantum simulation
• Ultracold molecules
• Quantum magnetism

Background:

• Long-range and anisotropic dipolar interactions significantly alter particle dynamics in periodic potentials.
• Understanding these interactions is crucial for developing advanced quantum simulation platforms.

Purpose of the Study:

• To realize and study a generalized t-J model incorporating dipolar interactions using ultracold fermionic molecules.
• To investigate the interplay between tunable dipolar Ising and spin-exchange couplings, molecular motion, and coherent spin dynamics.

Main Methods:

• Utilized a system of ultracold fermionic molecules with spin encoded in rotational states.
• Independently tuned dipolar Ising and spin-exchange couplings and molecular motion.
• Employed Ramsey spectroscopy to observe and model spin dynamics.

Main Results:

• Observed and modeled interaction-driven contrast decay in coherent spin dynamics.
• Demonstrated that contrast decay is strongly dependent on the anisotropy of couplings and molecular motion.

Conclusions:

• This work establishes a highly tunable molecular platform for exploring kinetic spin dynamics and quantum magnetism.
• The findings provide insights into regimes challenging for existing numerical and analytical methods.