All-optical THz wave switching based on CH₃NH₃PbI₃ perovskites

Area of Science:

• Optoelectronics
• Materials Science
• Terahertz Technology

Background:

• Terahertz (THz) waves are crucial for various applications, including imaging and spectroscopy.
• Controlling THz wave propagation optically offers precise and non-invasive modulation capabilities.
• Silicon-based devices are widely used, but integrating them with novel materials like perovskites can unlock new functionalities.

Purpose of the Study:

• To propose and investigate hybrid silicon-perovskite structures for optically controllable THz wave switching.
• To evaluate the performance of these devices across a broad THz spectral range (0.2-2 THz).
• To identify optimal fabrication methods for stable and efficient THz switching devices.

Main Methods:

• Fabrication of hybrid silicon-perovskite structures using different solution processing techniques.
• Optical control using a 532-nm laser to generate photoexcited free carriers.
• Characterization of THz wave amplitude modulation depth and spectral response.

Main Results:

• Achieved significant THz amplitude modulation depth of up to 68% at a laser irradiance of 1.5 W/cm².
• Demonstrated effective optical switching over a broad THz frequency range (0.2-2 THz).
• Identified a one-step solution processing method yielding a stable and highly efficient THz switch.

Conclusions:

• Hybrid silicon-perovskite structures are promising for optically controlled THz wave switching.
• The developed devices exhibit high modulation depth and broad spectral applicability.
• This work highlights the potential of perovskites beyond photovoltaics, extending to THz optoelectronics.