From the university of Southampton, UK and France Bohr dodd Optique institute researchers have found that by controlling the light to make silicon chips for programmable logic. Silicon photonics is the foundation of the next generation of chip technology and optical communication technology, positioning in the optical interconnection, microwave photonic circuits and emerging applications such as integrated optical sensors.
Researchers believe that, although the photon chip are generally "hard-wired", but by the reconstruction of the optical device can make the light more flexible, makes programmable optical circuit called a possibility. ", they say, usually using liquid crystal spatial light modulator or micro lens to realize independent control of pixels, these technologies to the development of optical brought a radical change, made in recent years in the holographic optical imaging optics, and a new adaptive optics applications."
Their latest research results to be published in the journal Optica, team used a multimode interference (MMI) equipment. But with the traditional fixed mode, they are using femtosecond laser to realize the dynamic mode conversion of MMI. Can realize effective modulation of the transmitted light, through the implementation model, part of the pattern is reflected.
By using a 1 x 2 MMI splitter and a projection of the disturbance of femtosecond laser design, realized the light route to a single export 97% efficiency, and makes the realization of programmable device. Team leading researchers, a postdoctoral fellow at the university of Southampton Roman Bruck commented, "our results proved by modulating the light to illuminate the chip to inherit the light path programmability. Integration of spatial light modulator makes the traditional silicon photonics device can be used as a generic refactoring device."
Published in the journal Optica described in the article, "in theory, through within a certain range of refractive index modulation can realize the complete control of the light propagation direction, the realization of this technique is similar to field programmable logic device (FPGA). In fact, as early as before, similar to the optical structure of FPGA has been some discussion, such as microwave and silicon nitride waveguide. The FPGA based on the mature silicon photonics platform all-optical analogues have been widely used, such as optical communications in the WDM and wavelength selection and routing, etc."
The practical application of the technology including the all-optical reconfigurable routers, optical networks of ultrafast optical modulator and optical switch and microwave photonic circuits and so on. Now you need to work is to develop these ideas as soon as possible into practical application.
"Functions"
In an interview with reporters, project leader, physics, astronomy professor at the university of Southampton, Otto Muskens professor and describes the latest progress in the study of the current market expectations. The backbone of the optical interconnection technology is becoming today's optical network technology. Chip level interconnect technology has a variety of technology to achieve so far, the specific implementation depends on whether the monochromatic light, and the complex light output you need independent transmission to the single output.
"A lot of functions can be implemented through traditional cascade of the device, such as array waveguide grating and interference device. But because of the traditional device size is larger, subject to effective size silicon optical chips, restricts their application in optical networks. But our method is different from the traditional, by using multi-mode control can make the device configuration is very compact. By perturbation model, can determine the direction of propagation of light. This concept is common, and is expected to be used to implement the highly flexible small router."
"At the moment we work more is still a fundamental research, the next need to new concepts into actual products and equipment. We believe that the optical control will be a feasible way to future, on the one hand because of the effective light source costs less and less, on the other hand the light source and the modulator can be integrated on a chip directly. This method could be applied in the next generation of ROADM."
"In addition, more work is needed to explore the technique of the concrete implementation mechanism. Because of this technology rely on external light source and digital micro mirror used for modulation, so it's the start application should be based on the development of laboratory equipment, will slowly turned to large-scale wafer processing and testing. In the end, we will to the technology field programmable logic devices, and the changing functions of the logic devices will no longer need a new design and manufacturing cycle. We are currently focusing on at Southampton silicon photoelectron planned for commercial promotion."
