Coupling a single atomic quantum bit to a high finesse optical cavity

Area of Science:

• Quantum Information Science
• Atomic Physics
• Cavity Quantum Electrodynamics

Background:

• Single trapped ions are promising candidates for quantum information processing.
• Optical cavities enhance light-matter interactions, crucial for quantum control.

Purpose of the Study:

• To achieve coherent coupling between a single Ca+ ion's S(1/2)-D(5/2) transition and an optical cavity.
• To deterministically couple the cavity mode to the ion's vibrational state.

Main Methods:

• Utilizing a single trapped Ca+ ion and a high-finesse optical cavity.
• Coherently coupling the ion's quadrupole transition to the cavity's standing wave field.
• Precisely controlling ion position and exciting specific vibrational transitions.

Main Results:

• Verified coherent coupling by observing the ion's response to intracavity field variations.
• Achieved deterministic coupling of the cavity mode to the ion's vibrational state.
• Demonstrated nanometer-precision control over ion positioning within the cavity.

Conclusions:

• The demonstrated coherent coupling is a significant step towards robust quantum bit encoding.
• Precise control over ion-cavity interactions opens avenues for advanced quantum computing and sensing applications.