Multicolored Switching for Optical Computer Applications

Multicolored optical switching opens new possibilities in advanced optical technologies

According to a report from Waseda University, opaque materials can transmit light when excited by a high-intensity laser beam, a process known as optical bleaching. This induces a nonlinear effect that temporarily alters material properties. When the laser is rapidly switched on and off, the effect can be dynamically controlled, paving the way for innovative optical technologies.

Multicolored optical switching has significant potential in fields like telecommunications and optical computing. However, most materials exhibit single-color optical nonlinearity under intense laser illumination, limiting their use in systems requiring multicolor switching capabilities. Current optical switches, based on microelectromechanical systems, have slow response times due to the need for electric voltage or current.

Addressing this challenge, a team of researchers led by Professor Junjun Jia from Waseda University, in collaboration with experts from Zhejiang University, Chubu University, and the National Institute of Advanced Industrial Science and Technology, investigated multivalley optical switching in germanium (Ge) films. They focused on how intense laser irradiation induces ultrafast optical switching across multiple wavelengths in Ge, a multivalley semiconductor. Their study showcased efficient multicolored optical switching using a single-color pulse laser, potentially overcoming traditional limitations.

The research, published in Physical Review Applied on February 24, 2025, highlights the promising advancements in multicolored optical switching. By exploring the multivalley optical switching phenomenon in Ge films, the team demonstrated the feasibility of achieving dynamic control over optical properties across various wavelengths. This breakthrough could lead to the development of faster and more versatile optical switching technologies for diverse applications.

With the ability to achieve multicolored optical switching using a single-color pulse laser, the researchers have opened up new avenues for enhancing optical computing and telecommunication systems. By harnessing the unique properties of germanium and leveraging intense laser irradiation, the team has shown that multicolored optical switching can be achieved efficiently and effectively, offering a potential solution to the limitations of traditional single-color optical nonlinearities.