Researchers have designed a new chip-integrated light source that can transform infrared wavelengths into visible wavelengths, which have been difficult to produce with technology based on silicon chips. This flexible approach to on-chip light generation is poised to enable highly miniaturized photonic instrumentation that is easy to manufacture and rugged enough to use outside the lab.

In Optica, The Optical Society’s (OSA) journal for high impact research, investigators from the National Institute of Standards and Technology (NIST), University of Maryland, and University of Colorado describe their new optical parametric oscillator (OPO) light source and show that it can produce output light that is a very different color, or wavelength, than the input light. In addition to creating light at visible wavelengths, the OPO simultaneously generates near-infrared wavelengths that can be used for telecommunication applications.

«Our power-efficient and flexible approach generates coherent laser light across a range of wavelengths wider than what is accessible from direct chip-integrated lasers,» said research team leader Kartik Srinivasan. «The on-chip creation of visible light can be used as part of highly functional compact devices such as chip-based atomic clocks or devices for portable biochemical analyses. Developing the OPO in a silicon photonics platform creates the potential for scalable manufacturing of these devices in commercial fabrication foundries, which could make this approach very cost-effective.»

Exploiting nonlinear processes

Although the response of a material to light typically scales linearly, material properties can change more rapidly in response to light at high power, which creates various nonlinear effects. OPOs are a type of laser that use nonlinear optical effects to create a very broad range of output wavelengths.

The researchers wanted to figure out how to take laser emission at a wavelength readily available with compact chip lasers and combine it with nonlinear nanophotonics to generate laser light at wavelengths that are otherwise hard to reach with silicon photonics platforms.

Story Source: Materials provided by The Optical Society. Note: Content may be edited for style and length.