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We present measurements of the Gouy phase accumulation for the fundamental mode of an astigmatic Fabry-Perot cavity over 70 % of its stability range. The method is based on simultaneous measurement of the resonant frequencies of the fundamental mode and
Traceability of interferometric form measurements requires characterization of the reference wavefront. We investigate absolute tests for spherical surfaces where the form errors of both reference and test surface are estimated by minimizing the difference
Over the past two decades, the Sensor Science Division at the National Institute of Standards and Technology (NIST) has developed extensive capabilities for the characterization of the infrared optical properties of materials and components. These include
High-precision spheres have many applications in precision engineering and metrology, such as the calibration of transmission spheres for interferometry, density standards for mass metrology, and spherical gyroscope rotors. For these applications it is
Fahmida Ferdous, Houxun H. Miao, Pei-Hsun Wang, Daniel E. Leaird, Kartik Srinivasan, Lei Chen, Vladimir Aksyuk, Andrew M. Weiner
Recent investigations of microcavity frequency combs based on cascaded four-wave mixing have revealed a link between the evolution of the optical spectrum and the observed temporal coherence. Here we study a silicon nitride microresonator for which the
We present a technique called coupled-cavity ring-down spectroscopy (CC-RDS) for controlling the finesse of an optical resonator. Applications include extending the sensitivity and dynamic range of a cavity-enhanced spectrometer, as well as widening the
William Sparks, Thomas Germer, John MacKenty, Frans Snik
We present an approach to spectropolarimetry which requires neither moving parts nor time dependent modulation, and which o ers the prospect of achieving high sensitivity. The concept, which is one of those generically known as channeled polarimetry, is to
Thomas Gerrits, Nick Thomas-Peter, James Gates, Adriana E. Lita, Benjamin Metcalf, Brice R. Calkins, Nathan A. Tomlin, Anna E. Fox, Antia A. Lamas-Linares, Justin Spring, Nathan Langford, Richard P. Mirin, Peter Smith, Ian Walmsley, Sae Woo Nam
We demonstrate the operation of an integrated photon number resolving transition edge sensor (TES), operating in the telecom band at 1550 nm, employing an evanescently coupled design that allows the detector to be placed at arbitrary locations within a
Zachary H. Levine, Thomas Gerrits, Alan L. Migdall, Daniel V. Samarov, Brice R. Calkins, Adriana E. Lita, Sae Woo Nam
Improving photon-number resolution of single-photon sensitive detectors is important for many applications, as is extending the range of such detectors. Here we seek improved resolution for a particular Superconducting Transition-Edge Sensor (TES) through
Localizing a fluorescent particle by scanning a focused laser in its vicinity and analyzing the detected photon stream provides real-time information for a modern class of feedback control systems for particle tracking and trapping. We present a simple
Behrang H. Hamadani, John F. Roller, Brian P. Dougherty, Howard W. Yoon
An absolute differential spectral response measurement system for solar cells is presented. The system couples an array of light emitting diodes (LEDs) with an optical waveguide to provide large area illumination. Two unique yet complementary measurement
Testing standards are more fundamental from a metrological perspective and less controversial from an industrial perspective than product standards, representing a path of less resistance towards the standardization and commercialization of lab on a chip
Optical pulse propagation with group velocities larger than the speed of light in vacuum, c, or negative, have been demonstrated theoretically and experimentally in a variety of systems [15]. The anomalous dispersion required for generating fast light
David F. Phillips, Alexander G. Glenday, Chih-hao Li, Claire E. Cramer, Gabor Furesz, Guoquing Chang, Andrew Benedick, Li-Jin Chen, F X. Kaertner, Sylvain G. Korzennik, Dimitar Sasselov, Andrew Szentgyorgyi, Ronald L. Walsworth
We deployed two wavelength calibrators based on laser frequency combs ("astro-combs") at an astronomical observatory. One astro-comb operated over a 100 nm band in the deep red ( 800 nm) and a second operated over a 20 nm band in the blue ( 400 nm). We
Kevin L. Silverman, Mingming M. Feng, Richard P. Mirin, Steven T. Cundiff
Passively mode-locked semiconductor lasers with self-assembled quantum dot active regions can be operated in exotic output modes, stabilized by the complex gain and absorption dynamics inherent in these structures. One such device emits dark pulses - sharp
Kevin O. Knabe, Paul A. Williams, Fabrizio R. Giorgetta, Chris Armacost, Michael Radunsky, Nathan R. Newbury
The instantaneous optical frequency of an external-cavity quantum cascade laser (QCL) is characterized by comparison to a near-infrared frequency comb. Fluctuations in the instantaneous optical frequency are analyzed to determine the frequency noise power
Fabrizio R. Giorgetta, Esther Baumann, Kevin O. Knabe, Ian R. Coddington, Nathan R. Newbury
We demonstrate a FMCW Lidar with a frequency-calibrated laser modulated over 1 THz at ~1 kHz modulation frequency. Range to a diffuse target is measured at 0.5 ms intervals with 150 υm resolution and ~1 υm precision. Work of the U.S. government, not
Fan Zhang, Andrew J. Allen, Lyle E. Levine, Jan Ilavsky, Gabrielle G. Long
Ultra-small-angle X-ray scattering—X-ray photon correlation spectroscopy (USAXS-XPCS) is a novel measurement technique for the study of equilibrium and slow nonequilibrium dynamics in disordered materials. This technique fills an existing gap between the
We report on the four-wave mixing of superluminal pulses, in which both the injected and generated pulses involved in the process propagate with negative group velocities. Generated pulses with negative group velocities of up to vg = −c/880 are
Arvind Balijepalli, Thomas W. LeBrun, Jason J. Gorman
We demonstrate an increase in trapping lifetime for optically trapped nanoparticles by more than an order of magnitude using feedback control. This has been demonstrated through simu- lation and experimental results for 100, nm gold particles and 350 nm
Richard M. Silver, Jing Qin, Bryan M. Barnes, Hui Zhou, Ronald G. Dixson, Francois R. Goasmat
There has been much recent work in developing advanced optical metrology applications that use imaging optics for critical dimension measurements, defect detection and for potential use with in-die metrology applications. Sensitivity to nanometer scale
David A. Long, A. Cygan, Roger D. van Zee, Mitchio Okumura, C. E. Miller, D Lisak, Joseph T. Hodges
This Frontiers article describes frequency-stabilized cavity ring-down spectroscopy (FS-CRDS), an ultraprecise refinement of conventional cw-CRDS. We review the technique and highlight some recent studies which have utilized FS-CRDS to perform precision
Heather J. Patrick, Leonard M. Hanssen, Jinan Zeng, Thomas A. Germer
We have measured angle- and polarization-resolved, hemispherical bidirectional reflectance distribution function (BRDF) for two types of graphite used in the fabrication of high temperature fixed point (HTFP) blackbody cavities. Measurements were made at
The evolution of a Stokes vector through depolarizing media is considered. A general form for the differential matrix is derived that is appropriate in the presence of depolarization, and is parameterized in a manner that ensures that it yields, upon