Related papers: Long-range, phase-and-polarization diversity coher…
Optical cavities provide high sensitivity to dispersion since their resonance frequencies depend on the index of refraction. We present a direct, broadband, and accurate measurement of the modes of a high finesse cavity using an optical…
We implement a real-time coherent transceiver with fast streaming outputs for environmental sensing. Continuous sensing using phase and equalizer outputs over 12800km of a submarine cable is demonstrated to enable time resolved spectroscopy…
We describe a technique for measuring the complex reflectivity of an optical cavity with a resonant local oscillator laser and an auxiliary probe laser, each coupled via opposite ends of the cavity. A heterodyne sensing scheme is then used…
In this paper, we show how the combined use of low coherence interferometry, balanced detection and data processing comparable to that used in Fourier transform spectrometry allows us to characterize with ultimate resolutions (sub-ppm in…
We describe a setup based on Michelson interferometry for coherent measurements of the backscattered light from a low roughness optical surface under test. Special data processing was developed for the extraction of the useful signal from…
A bidirectional all polarization maintaining fiber laser as a highly sensitive sensor for rotation is presented. This sensor is based on intracavity phase interferometry with application in inertial sensing, magnetometry, displacements and…
We report on a novel detection system for collinear laser spectroscopy which provides an almost $4\pi$ solid angle for fluorescence photon detection by employing curved surface mirrors. Additional parabolic angular filters offer passive…
As telescopes get larger, the size of a seeing-limited spectrograph for a given resolving power becomes larger also, and for ELTs the size will be so great that high resolution instruments of simple design will be infeasible. Solutions…
By means of C-OTDR (Correlation - Optical Time Domain Reflectometry), we measured the latency of100 km fiber with an accuracy of a few picoseconds. Based on iterating 49 measurements, we calculated a standard deviation of 12 ps between the…
Non-contact measurement of the refractive index and thickness of multilayer biological tissues is of great significance for biomedical applications and can greatly improve medical diagnosis and treatment. In this work, we introduce a…
Due to high dynamic range and ease of use, continuous wave terahertz spectroscopy is an increasingly popular method for optical characterization of components used in cosmic microwave background (CMB) experiments. In this work, we describe…
Optical spectroscopy is a fundamental tool in numerous areas of science and technology. Much effort has focused on miniaturizing spectrometers, but thus far at the cost of high spectral resolution and broad operating range. Here, we…
The speckle pattern produced when a laser is scattered by a disordered medium has recently been shown to give a surprisingly accurate or broadband measurement of wavelength. Here it is shown that deep learning is an ideal approach to…
Highly coherent wave is favorable for applications in which phase retrieval is necessary, yet a high coherent wave is prone to encounter Rayleigh fading phenomenon as it passes through a medium of random scatters. As an exemplary case,…
A general-purpose all-fiber spectrometer is demonstrated to overcome the trade-off between spectral resolution and bandwidth. By integrating a wavelength division multiplexer with five multimode optical fibers, we have achieved 100 nm…
Laser phase noise remains a limiting factor in many experimental settings, including metrology, time-keeping, as well as quantum optics. Hitherto this issue was addressed at low frequencies, ranging from well below 1 Hz to maximally 100…
Context. The next generation of space-borne instruments dedicated to the direct detection of exoplanets requires unprecedented levels of wavefront control precision. Coronagraphic wavefront sensing techniques for these instruments must…
Recently, novel imaging techniques based on the 'memory-effect' speckle-correlations have enabled diffraction-limited imaging through scattering layers and around corners. These techniques, however, are currently limited to imaging only…
We propose and experimentally demonstrate a fiber spectrum analyzer based on a planar waveguide chip butt-coupled with an input fiber and aligned to a standard camera without any free-space optical elements. The chip consists of a…
Fiber optic sensing is becoming an important means to physically secure today's network infrastructure. However, a network-wide deployment of the monitors will require cost reduction of the interrogator system, which can only be achieved by…