Song’s device removes that limitation by reaching the same interferometer signal with less light at the detectors, which leaves room to increase the signal to noise ratio by continuing to add laser power.īottom line: “If the same amount of power reaches the detector in Meiting’s weak value device as in a traditional interferometer, Meiting’s device will always have a better signal to noise ratio,” Cardenas says. But there’s actually a limitation, Cardenas says, because the traditional detectors used with interferometers can handle only so much laser power before becoming saturated, at which point the signal to noise ratio can’t be increased. With traditional interferometers, the signal to noise ratio can be increased, resulting in more meaningful input, by simply cranking up the laser power. “No one has really talked about wavefront engineering on a photonic chip.” “This is one of the novelties of the paper,” Cardenas says. Instead of using a set of tilted mirrors to bend light and create an interference pattern, Song’s device includes a waveguide engineered to propagate the wavefront of an optical field through the chip.
The device Song created does not look like a traditional interferometer. Song “distilled all of this and put it into a photonic chip.” The chip (right) requires only a single microscope. Traditional interferometry (left) requires an elaborate set up of mirrors and laser systems all very painstakingly and carefully aligned,” Cardenas says. “And by having the interferometer on a chip, you can put it on a rocket, or a helicopter, in your phone-wherever you want-and it will never be misaligned.” “Meiting distilled all of this and put it into a photonic chip,” Cardenas says. The concept has been demonstrated before, “but it’s always with a large setup in a lab with a table, a bunch of mirrors and laser systems, all very painstakingly and carefully aligned,” Cardenas says. Weak value amplification is based on the quantum mechanics of light, and basically involves directing only certain photons that contain the information needed, to a detector.
It’s not exactly free since you sacrifice power, but it’s almost for free, because you can amplify the signal without adding noise-which is a very big deal,” Cardenas says. “Basically, you can think of the weak value amplification technique as giving you amplification for free. Therefore, they were able to prove the theoretical feasibility of integrating weak value amplification on a photonic chip. They have applied mode analysis in a novel way on free space interferometer with weak value amplification, which bridged the gap between free space and waveguide weak value amplification. Jordan and his group have been studying weak value amplification for over a decade. Jaime Cardenas (left) and Meiting Song in the Cardenas Lab at Rochester’s Institute of Optics. University of Rochester researchers for the first time package a way of amplifying interferometric signals using inverse weak value amplification -without increase in extraneous input or “noise”-on an integrated photonic chip.īy merging two or more sources of light, interferometers create interference patterns that can provide remarkably detailed information about everything they illuminate, from a tiny flaw on a mirror, to the dispersion of pollutants in the atmosphere, to gravitational patterns in far reaches of the Universe. Researchers at University of Rochester’s Institute of Optics for first time distill novel interferometry into a photonic device.
Potential applications include more sensitive devices for measuring tiny flaws on mirrors, or dispersion of pollutants in the atmosphere, and ultimately, quantum applications. A 2 mm by 2 mm integrated photonic chip developed by Jaime Cardenas, assistant professor of optics, and PhD student Meiting Song (lead author) will make interferometers-and therefore precision optics-even more powerful.