Tunable Terahertz Metamaterial with Electromagnetically Induced Transparency Characteristic for Sensing Application

Area of Science:

• Terahertz (THz) photonics and metamaterials.
• Micro-Electro-Mechanical Systems (MEMS) integration.
• Advanced optical and sensing applications.

Background:

• Terahertz (THz) technology requires tunable and responsive metamaterials.
• Existing metamaterials often lack active tunability and efficient sensing capabilities.
• Electric split-ring resonator (eSRR) structures offer unique electromagnetic responses.

Purpose of the Study:

• To design and demonstrate a MEMS-based tunable terahertz metamaterial (TTM).
• To investigate the electromagnetic responses, including polarization dependence and electromagnetically induced transparency (EIT).
• To evaluate the TTM's potential as a refractive index sensor.

Main Methods:

• Fabrication of a TTM device using MEMS technology with inner triadius and outer eSRR structures.
• Systematic variation of geometrical parameters (length, radius, height) to optimize TTM design.
• Analysis of electromagnetic responses and sensing performance metrics (sensitivity, Q-factor, FOM).

Main Results:

• Achieved a resonance tuning range of 0.32 THz by adjusting structural dimensions.
• Demonstrated polarization-dependent and EIT characteristics.
• Calculated a high sensitivity of 0.379 THz/RIU for refractive index sensing, with average Q-factor and FOM values of 66.01 and 63.83, respectively.

Conclusions:

• The MEMS-based TTM exhibits tunable resonance, polarization dependence, and EIT.
• The device shows significant potential for high-performance refractive index sensing.
• The TTM is suitable for diverse THz applications like tunable filters, absorbers, sensors, and optical switches.