Related papers: Coexisting frequency combs spaced by an octave in …
The frequency noise power spectral density of a free-running quantum cascade laser frequency comb is investigated. A plateau is observed at high frequencies, attributed to the quantum noise limit set by the Schawlow-Townes formula for the…
Quantum cascade laser (QCL) frequency combs have revolutionized mid-infrared (MIR) spectroscopy by their high brightness and fast temporal resolution, and are a promising technology for fully-integrated and cost-effective sensors. As for…
Quantum cascade lasers are compact sources capable of generating frequency combs. Yet key characteristics - such as optical bandwidth and power-per-mode distribution - have to be improved for better addressing spectroscopy applications.…
Quantum cascade lasers (QCLs) represent a fascinating accomplishment of quantum engineering and enable the direct generation of terahertz (THz) frequency radiation from an electrically-biased semiconductor heterostructure. Their large…
The generation of optical frequency combs via direct electrical pumping of semiconductor lasers is an attractive alternative to the well-established mode-locked laser sources in terms of compactness, robustness and integrability. However,…
Harmonic frequency combs, in which the lasing modes are separated by a period of tens of free spectral ranges from each other, have been recently discovered in quantum cascade lasers (QCLs). There is an ongoing debate how the harmonic combs…
THz quantum cascade lasers (QCLs) based on double metal waveguides feature broadband and high-temperature devices for use in spectroscopy and sensing. However, their extreme field confinement produces poor output coupling efficiencies and…
Rapid development of Fabry-Perot quantum cascade laser frequency combs has converted them from laboratory devices to key components of next-generation fast molecular spectrometers. Recently, free-running ring quantum cascade lasers allowed…
Quantum cascade laser (QCL) frequency combs are a promising candidate for chemical sensing and biomedical diagnostics, requiring only milliseconds of acquisition time to record absorption spectra without any moving parts. They are…
One salient characteristic of Quantum Cascade Laser (QCL) is its very shor gain recovery time that so far thwarted the attempts to achieve self-mode locking of the device into a train of single pulses. We show theoretically that four wave…
Terahertz quantum cascade lasers (THz QCLs) are chip-scale semiconductor lasers operating in the frequency range between 1-6 THz, useful as compact sources for spectroscopy, communications, and non-destructive imaging and testing. Here, we…
We present detailed studies of the coherence properties of an ultra-broadband super-continuum, enabled by a new approach involving continuous wave laser sources to independently probe both the amplitude and phase noise quadratures across…
Low noise and high repetition rate optical frequency combs are desirable for many applications from timekeeping to precision spectroscopy. For example, gigahertz repetition rate sources greatly increase the acquisition speed of spectra in a…
We demonstrate a frequency comb spanning an octave via the parametric process of cascaded four-wave mixing in a monolithic, high-Q silicon nitride microring resonator. The comb is generated from a single-frequency pump laser at 1562 nm and…
We report a comprehensive study of low-power, octave-bandwidth, single-soliton microresonator frequency combs in both the 1550 nm and 1064 nm bands. Our experiments utilize fully integrated silicon-nitride Kerr microresonators, and we…
A compact and robust coherent laser light source that provides spectral coverage from the ultraviolet to infrared is desirable for numerous applications, including heterodyne super resolution imaging[1], broadband infrared microscopy[2],…
Optical frequency combs paved the way for fast and compact multi-component optical chemical analysis due to their broadband spectra. Dual-comb spectrometers embody this technology, but their design requires a pair of matched combs, adding…
Terahertz sources based on intra-cavity difference-frequency generation in mid-infrared quantum cascade lasers (THz DFG-QCLs) have recently emerged as the first monolithic electrically-pumped semiconductor sources capable of operating at…
We report on a waveguide engineering technique that enables the generation of a bandwidth up to 1 THz and record ultra-short pulse length of 2.5 ps in injection seeded terahertz quantum cascade lasers. The reported technique is able to…
We measure the inter-modal phase relation of a quantum cascade laser frequency comb operating at 8 um using a coherent beatnote spectroscopy. We find these phases to be reproducible after cycling the power of the device, and to be smoothly…