New photonic chip spawns nested topological frequency comb

Phys.org  June 20, 2024 On-chip frequency combs have relied predominantly on single-ring resonators. A team of researchers in the US (University of Maryland, University of Illinois, Northeastern University) experimentally demonstrated the generation of topological frequency combs, in a two-dimensional lattice of hundreds of ring resonators that hosts fabrication-robust topological edge states with linear dispersion. By pumping these edge states, they demonstrated the generation of a nested frequency comb that showed oscillation of multiple edge state resonances across ≈40 longitudinal modes and was spatially confined at the lattice edge. According to the researchers their results provide an opportunity to explore the […]

Research team realizes magnonic frequency comb

Phys.org  April 1, 2024 A direct analog of frequency combs in the magnonic systems has not been demonstrated to date. Researchers in China generated a new magnonic frequency comb in the resonator with giant mechanical oscillations through the magnomechanical interaction. It contained up to 20 comb lines, which were separated by the mechanical frequency of 10.08 MHz. The thermal effect based on the strong pump power induced the cyclic oscillation of the magnon frequency shift, which led to a periodic oscillation of the magnonic frequency comb. They demonstrated the stabilization and control of the frequency spacing of the magnonic frequency […]

New microchip links two Nobel Prize-winning techniques

Science Daily  March 22, 2023 Mechanical frequency combs are poised to bring the applications and utility of optical frequency combs into the mechanical domain. So far, their main challenge has been strict requirements on drive frequencies and power, which complicate operation. An international team of researchers (the Netherlands, USA – NIST) has demonstrated a straightforward mechanism to create a frequency comb consisting of mechanical overtones (integer multiples) of a single eigenfrequency, by monolithically integrating a suspended dielectric membrane with a counter-propagating optical trap. The periodic optical field modulated the dielectrophoretic force on the membrane at the overtones of a membrane’s […]

An on-chip time-lens generates ultrafast pulses

Science Daily  November 11, 2022 Integrated femtosecond pulse and frequency comb sources are critical components for a wide range of applications, including microwave photonics, communications, lidar, optical computing, and astronomy among other things. A team of researchers in the US (Harvard University, UCLA, Columbia University, industry) has demonstrated a chip-scale femtosecond pulse source implemented on an integrated lithium niobate photonic platform forming a time-lens system. The device was driven by a continuous-wave distributed feedback laser chip and controlled by a single continuous-wave microwave source without the need for any stabilization or locking. They measured femtosecond pulse trains with a 30-gigahertz […]

Scientists greatly expand the frequencies generated by a miniature optical ruler

Phys.org  February 23, 2022 A team of researchers in the US (NIST, University of Maryland) has produced a microcomb using two lasers, each generating a different frequency of light, instead of just one. They found that through a complex series of interactions with the soliton light circulating in the microring resonator, the second laser induced two new sets of teeth, or evenly spaced frequencies, that are replicas of the original set of teeth but shifted to higher and lower frequencies. The lower frequency set lies in the infrared part of the spectrum, while the other is at much high frequencies, […]

Development of magneto-optic effect measurement device using dual-comb spectroscopy

Phys.org  November 19, 2019 Researchers in Japan developed a desktop prototype magneto-optic effect measurement device capable of evaluating the characteristics of magnetic materials with improved optical system and signal detection system its measurement performance greatly exceeds conventional measurement methods. It has magneto-optic effect measurement resolution of 0.01 degree, a wavelength resolution of 0.01 nanometer and capable of high-speed measurement through batch measurements of all wavelength components. A major feature of the prototype is its capability to measure the phase difference of light in addition to its intensity ratio. It is expected to become an important new tool for the precise […]

Combs of light for molecules

Nanowerk  March 7, 2019 Researchers in Germany review the developments and prospects in the emerging and quickly advancing field of atomic and molecular broadband spectroscopy with frequency combs. The past decade has witnessed remarkable progress in laser frequency comb generators dedicated to broadband spectroscopy, especially in the molecular-fingerprint mid-infrared (2–20 µm) region and the ultraviolet range (<400 nm). Existing spectrometers and spectrometric techniques have been adapted and improved to make the most of such sources (mode-locked lasers, nonlinear frequency conversion, microresonators, electro-optic modulators, semi-conductor lasers etc.), while entirely new comb-enabled approaches and instruments have been explored…read more. TECHNICAL ARTICLE