Separation of Time Scales in a Quantum Newton's Cradle

Area of Science:

• Quantum physics
• Condensed matter physics
• Ultracold atoms

Background:

• Understanding quantum dynamics is crucial for developing quantum technologies.
• Bragg spectroscopy and quantum Newton's cradle experiments probe many-body systems.
• Modeling strongly interacting one-dimensional boson systems presents significant theoretical challenges.

Purpose of the Study:

• To provide detailed modeling of Bragg pulses in one-dimensional strongly repulsive Bose systems.
• To investigate the time evolution of local density and momentum distributions post-pulse.
• To explore the effects of finite interaction strengths on system dynamics.

Main Methods:

• Exact techniques for modeling quantum systems.
• Time-dependent Hartree-Fock analysis for finite interactions.
• Bosonization-refermionization techniques for one-dimensional systems.

Main Results:

• Detailed modeling of Bragg pulse dynamics in one-dimensional Bose systems.
• Reconstruction of post-pulse time evolution, including local density and momentum distributions.
• Observation of distinct time scales: rapid, trap-insensitive relaxation followed by slow, periodic in-trap dynamics.
• Analysis of finite interaction strengths using advanced theoretical methods.

Conclusions:

• The study reveals a clear separation of time scales in the dynamics of strongly repulsive bosons after a Bragg pulse.
• Rapid relaxation occurs immediately after the pulse and is insensitive to trapping potentials.
• Slower, periodic behavior characterizes the system's evolution within the trap over longer timescales.