Single-atom-resolved fluorescence imaging of an atomic Mott insulator

Area of Science:

• Quantum optics
• Quantum information processing
• Atomic physics

Background:

• Single quantum particle detection is crucial for quantum optics and information processing.
• Extending detection to strongly correlated quantum systems for in situ imaging has been a long-standing goal.

Purpose of the Study:

• To demonstrate fluorescence imaging of strongly interacting bosonic Mott insulators with single-atom and single-site resolution.
• To enable precise in situ measurement of temperature and entropy in quantum systems.

Main Methods:

• Utilizing fluorescence imaging in an optical lattice.
• Reconstructing atom distribution and identifying individual excitations from images.
• Comparing radial density and variance distributions with theoretical models.

Main Results:

• Achieved single-atom and single-site resolution imaging of Mott insulators.
• Successfully reconstructed atom distribution and identified excitations with high fidelity.
• Enabled precise in situ temperature and entropy measurements from single images.
• Observed Mott-insulating plateaus with near-zero entropy and resolved high-entropy rings.
• Demonstrated Mott insulator melting with increasing temperature due to defect proliferation.

Conclusions:

• Single-atom resolution imaging provides unprecedented insight into quantum fluids.
• This technique allows for precise in situ characterization of quantum gases.
• Opens new avenues for manipulation, analysis, and applications of quantum gases, including novel cooling schemes.