The circulator is very important for optical routing in optical communication. However, they often require centimeter-level magnets, and these magnets are difficult to miniaturize for use in optical chips. Researchers at AMOLF, the University of Texas, and the City University of New York have circumvented this problem with microring resonator circulators. This circulator enables directional routing of light on laser pointers optical chips without using magnets.
The circulator can realize the transmission of information between two or more nodes in the network without any information loss. The circulator has several entrances and exits, and the light is routed in a specific way between these entrances and exits: the light entering a specific port will exit in the second port, but the light entering the second port will be in The third port shoots out, and so on.
Awlf group leader Ewold Verhagen said: "Light propagation is symmetrical in nature, which means that if light can travel from A to B, the reverse path is also feasible. We need a 'knowledge' that can break this symmetry "Usually this" trick "is to use centimeter-level magnets to transmit directivity and break the symmetry of laser pointer light propagation. But this system is difficult to miniaturize on a photonic chip."
Verhagen and his colleagues used a tiny glass to achieve the desired cyclical behavior through different "knacks". They let the light inside the ring interact with mechanical vibrations that have the same structure. Researchers used this principle in earlier research work to demonstrate one-way optical transmission. Verhagen states: "By controlling the light emitted by the laser, different color laser pointers can excite vibration by radiating pressure (but only when it is in the same direction as the controlling light wave). Because light propagates through the vibrating structure differently from static Moving structures, so optical forces break the symmetry of light propagation like a magnetic field. "
The challenge of current research is to decide which specific exit the light can be routed to. The light path in the refined control structure can ensure that the light from each input port can be emitted through the correct port.
AMOLF device is the first non-magnetic chip optical circulator. Although the research is fundamental in nature, it has many possible applications. Verhagen pointed out: "This device can be used to build chips that use light instead of electrons to transmit information and future quantum computers and communication networks. The implementation of circulator control provides the device with an additional laser pointer function, so the optical circuit can Feel free to reconfigure. "