cavitytrapping

Cavity trapping refers to a technique in atomic and molecular physics where neutral atoms or molecules are confined within an optical cavity—a structure formed by highly reflective mirrors. This method leverages the interaction between light and matter to localize particles within a small volume, enabling precise control over their motion and internal states.

The process typically involves cooling atoms or molecules using laser cooling techniques, such as Doppler cooling or magneto-optical trapping, before introducing them into the cavity. The cavity’s standing wave field, created by the interference of counter-propagating laser beams, exerts radiation pressure on the particles, trapping them near the nodes or antinodes of the field depending on the polarization and detuning of the light. This confinement allows for long interaction times with the cavity field, enhancing processes like spontaneous emission, stimulated emission, or coherent scattering.

Cavity trapping is particularly useful in quantum optics, quantum information science, and precision measurements. It enables the study of cavity quantum electrodynamics (QED), where strong coupling between light and matter can lead to phenomena such as vacuum Rabi splitting or the formation of polaritons. Additionally, it facilitates experiments in quantum simulation, where trapped particles can model complex physical systems.

The technique also finds applications in atomic clocks, where cavity-trapped atoms can achieve high stability and accuracy due to reduced motional broadening. Challenges in cavity trapping include minimizing losses from cavity decay, managing heating effects, and ensuring uniform trapping across large ensembles of particles. Advances in mirror coatings, laser stabilization, and cryogenic techniques continue to improve the efficiency and scalability of cavity trapping systems.