Radio Frequency Tunable Oscillator Device Based on a SmB_{6} Microcrystal

Area of Science:

• Condensed Matter Physics
• Materials Science
• Electronics

Background:

• Traditional radio frequency tunable oscillators often have complex structures and large footprints.
• Samarium Hexaboride (SmB_{6}) is a strongly correlated Kondo insulator with a unique topological surface state.

Purpose of the Study:

• To investigate the potential of SmB_{6} as a current-controlled oscillator.
• To explore the nonlinear dynamics of SmB_{6} for signal generation applications.

Main Methods:

• Utilized a 100 μm piece of SmB_{6} as the active component.
• Adjusted a direct current (dc) bias to control oscillation frequency and amplitude.
• Compared experimental results with a theoretical model of coupled surface and bulk states.

Main Results:

• Demonstrated SmB_{6} as a current-controlled oscillator operating in the 30 MHz frequency range.
• Achieved tunable ac voltage outputs from 20 Hz to 30 MHz by varying dc bias.
• Observed good agreement between experimental data and theoretical predictions.

Conclusions:

• SmB_{6} offers a novel, compact, and tunable platform for oscillator development.
• The device's performance is governed by the interplay of its surface and bulk electronic states.
• Scaling down crystal size may enable operation at higher frequencies, potentially in the terahertz (THz) regime.