Voltage-Controlled High-Bandwidth Terahertz Oscillators Based on Antiferromagnets.

Area of Science:

• Condensed Matter Physics
• Spintronics
• Materials Science

Background:

• Developing compact terahertz (THz) frequency generators and sensors is a significant technological hurdle.
• Noncollinear antiferromagnets (NCAFMs) are explored for their potential in THz applications.

Purpose of the Study:

• To demonstrate voltage-controlled frequency generation in the THz regime using NCAFMs.
• To investigate the tunability and dynamics of self-oscillations in kagome-structured NCAFMs.

Main Methods:

• Derivation of an effective theory to model spin-orbit torques (SOTs) and auto-oscillation dynamics.
• Analysis of reactive and dissipative SOT contributions.
• Investigation of chirality-dependent dynamics in NCAFMs.

Main Results:

• NCAFMs with kagome structure exhibit gapless self-oscillations.
• Frequencies are tunable from 0 Hz to the THz range via electrically induced SOTs.
• Chirality of the ground state critically influences excitation properties, enabling gapless oscillations in one case.

Conclusions:

• NCAFMs provide a promising platform for creating tunable THz functional components.
• These findings could help bridge the existing gap in THz technology.
• The study highlights the potential of NCAFMs for next-generation electronic devices.