Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Frequency combs are light sources with a spectrum that comprises a series of sharp, equally spaced lines. The frequencies of these lines are known to a very high degree of accuracy, which makes frequency combs an important tool in optical metrology and high-resolution spectroscopy.
A lab-scale proof-of-principle demonstration of a quantum network comprising one server chip and 20 client photonic chips implementing twin-field quantum key distribution shows excellent scalability and reliability and yields a pathway towards future large-scale networks.
Optical frequency combs enable simultaneous generation of low-noise phase calibration signals and RF local oscillators in radio astronomy receivers, improving stability and calibration with potential for future higher-frequency observations.
Frequency-comb enabled spectrum-correlation reflectometry employs a dual-sideband interleaved configuration to perform parallel multi-frequency interrogation, providing high frequency response over a broad optical spectral range.
Integrating a thin-film resistance thermometer above a high-Q SiN microresonator enables local temperature monitoring and active stabilization of its resonance wavelength. The emission wavelength of a distributed feedback laser locked to the microresonator fluctuates within 0.5 pm over a period of 50 h.
A hybrid optoelectronic synthesizer is developed that combines simplified optical frequency division with direct digital synthesis to generate tunable, low-phase-noise microwaves across the X-band. This approach also achieves high frequency stability while reducing the size, weight and power demands, paving the way for chip-scale photonic microwave sources.
An article in Nature Communications presents a spectral multiplication approach to obtain THz-tunable and broadband electro-optic combs using integrated multi-wavelength semiconductor lasers.
