skip to main content


Title: CMOS photonic integrated source of broadband polarization-entangled photons

We showcase a fully on-chip CMOS-fabricated silicon photonic integrated circuit employing a bidirectionally pumped microring and polarization splitter-rotators tailored for the generation of broadband (>9 THz), high-fidelity (90–98%) polarization-entangled photons. Spanning the optical C+L-band and producing over 116 frequency-bin pairs on a 38.4-GHz-spaced grid, this source is ideal for flex-grid wavelength-multiplexed entanglement distribution in multiuser networks.

 
more » « less
NSF-PAR ID:
10532574
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optica Quantum
Volume:
2
Issue:
4
ISSN:
2837-6714
Format(s):
Medium: X Size: Article No. 254
Size(s):
Article No. 254
Sponsoring Org:
National Science Foundation
More Like this
  1. A planar loaded microstrip network metamaterial on an irregular grid for modeling 2-D electromagnetic environment in TE polarization is presented. The technique is applied to a Luneburg lens example toward printed circuit implementation and verification. 
    more » « less
  2. ABSTRACT Interest in active metamaterial (MM) devices has recently increased due to their potential for tunable, switchable, and scalable optical responses. More specifically, a dynamic, on-chip MM polarizer has applications ranging from material characterization to sensing without the need for cumbersome external filters. This work demonstrates efforts to optimize MM devices for dynamic polarization filtering by combining elements from split-ring resonators, wire-pairs, and fishnet patterns. The polarization grid has been designed to operate under an applied voltage with simulated on/off ratios of 75% and dynamic polarization selectivity of 70%. Samples have been fabricated using epitaxial GaAs on sapphire with various n-type doping concentrations to approximate electrical tuning. 
    more » « less
  3. We calibrate and test a division-of-focal-plane red–green–blue (RGB) full-Stokes imaging polarimeter in a variety of indoor and outdoor environments. The polarimeter, acting as a polarization camera, utilizes a low dispersion microretarder array on top of a sensor with Bayer filters and wire-grid linear polarizers. We also present the design and fabrication of the microretarder array and the assembly of the camera and validate the performance of the camera by taking multiple RGB full-Stokes images and videos. Our camera has a small form factor due to its single-sensor design and the unique capability to measure the intensity, color, and polarization of an optical field in a single shot.

     
    more » « less
  4. Abstract

    We characterize the accuracy of linear-polarization mosaics made using the Atacama Large Millimeter/submillimeter Array (ALMA). First, we observed the bright, highly linearly polarized blazar 3C 279 at Bands 3, 5, 6, and 7 (3 mm, 1.6 mm, 1.3 mm, and 0.87 mm, respectively). At each band, we measured the blazar’s polarization on an 11 × 11 grid of evenly spaced offset pointings covering the full-width at half-maximum (FWHM) area of the primary beam. After applying calibration solutions derived from the on-axis pointing of 3C 279 to all of the on- and off-axis data, we find that the residual polarization errors across the primary beam are similar at all frequencies: the residual errors in linear polarization fractionPfracand polarization position angleχare ≲0.001 (≲0.1% of StokesI) and ≲ 1° near the center of the primary beam; the errors increase to ∼0.003–0.005 (∼0.3%–0.5% of StokesI) and ∼1°–5° near the FWHM as a result of the asymmetric beam patterns in the (linearly polarized)QandUmaps. We see the expected double-lobed “beam squint” pattern in the circular polarization (StokesV) maps. Second, to test the polarization accuracy in a typical ALMA project, we performed observations of continuum linear polarization toward the Kleinmann–Low nebula in Orion (Orion-KL) using several mosaic patterns at Bands 3 and 6. We show that after mosaicking, the residual off-axis errors decrease as a result of overlapping multiple pointings. Finally, we compare the ALMA mosaics with an archival 1.3 mm Combined Array for Research in Millimeter-wave Astronomy polarization mosaic of Orion-KL and find good consistency in the polarization patterns.

     
    more » « less
  5. Abstract

    This article critically reviews research on tornado theory and observations over the last decade. From the theoretical standpoint, the major advances have come through improved numerical-simulation models of supercell convective storms, which contain the tornado’s parent circulation. These simulations are carried out on a large domain (to capture the supercell’s circulation system), but with high grid resolution and improved representations of sub-grid physics (to capture the tornado). These simulations offer new insights into how and why tornadoes form in some supercells, but not others. Observational advances have come through technological improvements of mobile Doppler radars capable of rapid scanning and dual-polarization measurements, which offer a much more accurate view of tornado formation, tornado structure, and the tornado’s place within its parent supercell.

     
    more » « less