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Related papers: Continuous-wave coherent imaging with terahertz qu…

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We present a novel laser mode-locking scheme and discuss its unusual properties and feasibility using a theoretical model. A large set of single-frequency continuous-wave lasers oscillate by amplification in spatially separated gain media.…

Terahertz quantum cascade laser sources based on intra-cavity difference frequency generation from mid-IR devices are an important asset for applications in rotational molecular spectroscopy and sensing, beingthe only electrically pumped…

Low-noise lasers are of central importance in a wide variety of applications, including high spectral-efficiency coherent communication protocols, distributed fibre sensing, and long distance coherent LiDAR. In addition to low phase noise,…

High spectral purity frequency agile room temperature sources in the terahertz spectrum are foundational elements for imaging, sensing, metrology, and communications. Here we present a chip scale optical parametric oscillator based on an…

RF injection locking and spectral broadening of a terahertz (THz) quantum-cascade vertical-external-cavity surface-emitting laser (QC-VECSEL) is demonstrated. An intra-cryostat VECSEL focusing cavity design is used to enable continuous-wave…

Quantum sensing is highly attractive for accessing spectral regions in which the detection of photons is technically challenging: sample information is gained in the spectral region of interest and transferred via entanglement into another…

Quantum optical states which have no coherent amplitude, such as squeezed vacuum states, can not rely on standard readout techniques to generate error signals for control of the quadrature phase. Here we investigate the use of asymmetry in…

Quantum imaging with undetected photons spatially transfers amplitude and phase information from one spectral region of physical interest to another spectral region that is easy to detect. The photon energy of the two spectral regions can,…

Quantum Physics · Physics 2025-06-24 Mirco Kutas , Felix Riexinger , Jens Klier , Daniel Molter , Georg von Freymann

Dual-comb spectroscopy is a rapidly developing technique that enables moving parts-free, simultaneously broadband and high-resolution measurements with microseconds of acquisition time. However, for high sensitivity measurements and…

Instrumentation and Detectors · Physics 2019-08-14 Lukasz A. Sterczewski , Jonas Westberg , Gerard Wysocki

A novel lasing scheme for terahertz quantum cascade lasers, based on consecutive phonon-photon-phonon emissions per module, is proposed and experimentally demonstrated. The charge transport of the proposed structure is modeled using a rate…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 E. Dupont , S. Fathololoumi , Z. R. Wasilewski , G. Aers , S. R. Laframboise , M. Lindskog , A. Wacker , D. Ban , H. C. Liu

Providing phase stable laser light is important to extend the interrogation time of optical clocks towards many seconds and thus achieve small statistical uncertainties. We report a laser system providing more than 50 uW phase-stabilized UV…

The quantum cascade laser (QCL) has evolved to be a compact, powerful source of coherent mid-infrared (mid-IR) light. However, its fast gain dynamics strongly restricts the formation of ultrashort pulses. As such, the shortest pulses…

We demonstrate a technique for locking the frequency of a tunable diode laser to a ring-cavity resonator. The resonator is stabilized to a diode laser which is in turn locked to an atomic transition, thus giving it absolute frequency…

Optics · Physics 2009-11-07 Ayan Banerjee , Dipankar Das , Umakant D. Rapol , Vasant Natarajan

While characterization of coherent wavefields is essential to laser, x-ray and electron imaging, sensors measure the squared magnitude of the field, rather than the field itself. Holography or phase retrieval must be used to characterize…

Image and Video Processing · Electrical Eng. & Systems 2020-12-10 David J. Brady , Timothy J. Schulz , Chengyu Wang

We study the conditions for coherent radiation of an electron bunch driven by a counterpropagating strong pulsed electromagnetic plane wave. We derive the spectrum of the coherent radiation and show that it is emitted backwards with respect…

Plasma Physics · Physics 2024-04-17 Evgeny Gelfer , Alexander Fedotov , Ondrej Klimo , Stefan Weber

A new tuning mechanism is demonstrated for single-mode metal-clad plasmonic lasers, in which refractive-index of the laser's surrounding medium affects the resonant-cavity mode in the same vein as refractive-index of gain medium inside the…

Optics · Physics 2016-12-21 Chongzhao Wu , Yuan Jin , John L. Reno , Sushil Kumar

In the continuous-wave Detection and Ranging technology, simultaneous and accurate range and velocity measurements of an unknown target are typically achieved using a frequency-modulated continuous wave (FMCW) with a heterodyne receiver.…

In this work we develop an experimental procedure to interrogate the single- and multiphoton scattering matrices of an unknown quantum system interacting with propagating photons. Our proposal requires coherent state laser or microwave…

Quantum Physics · Physics 2017-10-17 Tomás Ramos , Juan José García-Ripoll

We report the observation of a clear single-mode instability threshold in continuous-wave Fabry-Perot quantum cascade lasers (QCLs). The instability is characterized by the appearance of sidebands separated by tens of free spectral ranges…

Real-time measurement of the absolute frequency of continuous-wave terahertz (CW-THz) waves is required for characterization and frequency calibration of practical CW-THz sources. We proposed a method for real-time monitoring of the…