IIT Delhi researchers develop advanced photodetector to boost high-speed optical communication

New Delhi (The Uttam Hindu): The Indian Institute of Technology Delhi (IIT Delhi) on Monday said that it has developed an advanced photodetector that could significantly improve high-speed optical communication.

The new device operates without an external power source and offers ultra-fast response and high sensitivity.

Photodetectors play a crucial role in optical communication by converting light signals into electrical signals, enabling high-speed data transfer.

However, traditional photodetectors require external power sources and often suffer from signal loss.

The newly developed metal-semiconductor-insulator-metal (MSIM) photodetector overcomes these limitations which makes it more efficient and reliable.

Unlike conventional silicon (Si) and gallium arsenide (GaAs)-based photodetectors, which need high biasing voltage and have limited flexibility, the new MSIM photodetector operates using photo-induced displacement current. This enhances its response time and efficiency.

The research, led by Dr. Rakesh Suthar (postdoctoral researcher) and Suryakant Singh, under the guidance of Professor Supravat Karak from the organic and hybrid electronic device laboratory, Department of Energy Science and Engineering, has been published in the prestigious journal Advanced Functional Materials.

Some of this work was also conducted at Nagoya University, Japan, under the JSPS Invitational Fellow program with Professor Kunio Awaga’s group.

“Our goal was to develop a high-speed, self-powered photodetector that can advance next-generation optical communication systems while ensuring energy efficiency,” said Professor Karak.

The research team used polymer PM6, acceptor Y6, and a dielectric parylene layer to create a device capable of generating fast transient photocurrent signals.

These signals have opposite polarity under light ON/OFF cycles, making them more easily distinguishable.

The device achieved an impressive cutoff frequency of 5.6 MHz, surpassing many existing organic photodetectors.

Additionally, the new photodetector has been successfully tested for real-time infrared (IR) communication using ASCII codes, demonstrating its potential for high-speed data transfer.

Its self-powered nature, combined with high sensitivity and fast response, makes it a promising technology for energy-efficient optoelectronic applications.

This innovation could also be valuable in quantum technology, particularly for single-photon detection and high-frequency communication.

The researchers plan to conduct further tests under the “Quantum Mission” project, which is led by IIT Delhi and funded by the Department of Science and Technology (DST).

“This research highlights the potential of organic semiconductors in developing energy-efficient and ultra-fast optoelectronic devices, significantly enhancing high-speed communication and sensing technologies,” Dr. Suthar said.