Anderson localization in a string of microwave cavities

Area of Science:

• Physics
• Condensed Matter Physics
• Wave Phenomena

Background:

• Microwave resonators are crucial components in various electronic devices.
• Understanding field distribution and localization is key to designing efficient resonators.
• Anderson localization describes the wave function localization in disordered systems.

Purpose of the Study:

• To investigate the field distributions and eigenfrequencies in a multi-cell microwave resonator.
• To explore the transition from extended to localized field distributions.
• To demonstrate the tunability of Anderson localization in a microwave cavity.

Main Methods:

• Fabrication of a 20-cell microwave resonator.
• Perturbation of the resonator's periodicity using external screws.
• Measurement of field distributions and eigenfrequencies.
• Analysis of frequency spectrum shifts.

Main Results:

• Observed a transition from extended to localized field distributions with increasing perturbation.
• Demonstrated signatures of Anderson localization for large perturbations.
• Showed that smaller perturbations result in extended or weakly localized fields.
• Confirmed tunability of localization length by adjusting screw penetration depth.
• Identified frequency spectrum shifts as evidence for Anderson localization.

Conclusions:

• The study successfully demonstrated and controlled Anderson localization in a tunable microwave resonator.
• The findings provide insights into wave localization phenomena in periodically perturbed systems.
• This work has implications for the design of novel microwave devices with tailored field localization properties.