New All-optical Diode Can Be Used In Miniature Optical Circuits

Science  and Technology Daily Beijing, March 18th (Reporter Liu Xia) According  to the report of the Physicist Organization Network on the 16th,  researchers at the National Physical Laboratory (NPL) in the United  Kingdom have developed an all-optical diode that can be used for new  diodes. In micro-photonic circuits, it is expected to provide inexpensive  and efficient photodiodes for micro-nano photonic chips, which will have  an important impact on photonic chips and photonic communications.

    Xiao  Yunfeng, a researcher at the Institute of Modern Optics at Peking  University, explained to the reporter of the Science and Technology  Daily: “Diodes can transmit current in one direction, but they block  reverse current and are fundamental components of almost all electronic  circuits, but existing optical diodes need to be large. Block magneto-optical crystals severely hinder their integration  at the micro/nano scale and become one of the major challenges in the  field of integrated photonics.”

    In the new study, the team led by Dr. Pascal Del Haye emitted light into a microresonator (glass microring on a silicon chip). Although  the microring diameter is only comparable to human hair, it allows  light to travel back and forth within the microring. Using the enhanced optical Kerr effect of microrings, the team created a new all-optical diode. The new diode can only transmit light in one direction and can be  integrated into micro-nano photonic circuits, thus overcoming the  limitation that diodes need large magneto-optic crystals.

    Del Haye emphasized that "these diodes are expected to provide  low-cost and efficient photodiodes for microchips. They will also pave  the way for new integrated photonic circuits that can be used for  optical calculations and may also have a significant impact on future  photonic communications systems."

    It  is reported that Chinese scientists have also achieved good results in  this area. For example, Dr. Dong Chunhua from the University of Science  and Technology of China used the micro-cavity interaction to obtain  all-optically controlled non-reciprocal microcavity devices, including  all-optical diodes and circulators. Wait.

    Xiao  Yunfeng said: "Although the latest research is not the first  all-optical diode, the obtained device has the characteristics of simple  operation and high isolation, so it is a very promising solution. Of  course, similar to the existing all-optical diode scheme, it is based on  resonance. The all-optical diodes of the cavity are often limited in bandwidth  and can only operate in a narrow resonant mode. Further research is  needed in the future to break through the limitations.”
 Science and Technology Daily