Gbps terahertz external modulator based on a composite metamaterial with a double-channel heterostructure

Area of Science:

• Physics
• Materials Science
• Electrical Engineering

Background:

• Terahertz (THz) research has grown significantly, driving demand for advanced modulation devices.
• Existing active THz modulators and switches struggle to meet system requirements.
• Double-channel heterostructures offer nanoscale two-dimensional electron gases (2DEGs) with high carrier concentration and mobility for novel THz devices.

Purpose of the Study:

• To develop an effective, ultrafast, and all-electronic grid-controlled THz modulator.
• To leverage composite metamaterial structures and double-channel heterostructures for enhanced THz modulation.
• To demonstrate a high-performance THz modulator for communication and imaging systems.

Main Methods:

• A composite metamaterial structure was designed, integrating a collective dipolar array with a double-channel heterostructure.
• Electrical control was employed to achieve resonant mode conversion between dipolar resonances.
• The modulator's performance was tested in real-time dynamic tests and a wireless free-space communication system.

Main Results:

• The THz modulator achieved a record 1 GHz modulation speed and 85% modulation depth.
• A significant phase shift of 1.19 radians was realized.
• A wireless THz communication system demonstrated 0.2 Gbps data transmission using the developed modulator.

Conclusions:

• The developed active composite metamaterial modulator is effective and ultrafast.
• This technology provides a basis for advanced THz wireless communication and imaging systems.
• The device overcomes limitations of current THz modulation technologies.