Devices for satellite-assisted quantum networks

Quantum networks, quantum nodes interconnected by quantum channels, offer powerful means of secure communications and quantum computations. They are crucial elements in a broad area of quantum technologies including quantum simulations and metrologies. In particular, quantum links with satellites take the network into a global or greater scale, extending the capability of transmitting information. It also provides experimental platforms of testing quantum physics in a relativistic regime. The realization of satellite-assisted quantum networks requires devices that are interfaced with quantum optical channels to satellites. This thesis discusses the development of four essential devices, three of which are in line with Canada's Quantum Encryption and Science Satellite (QEYSSat) mission. First, polarization-entangled photon sources are developed to transmit one of the paired photons over ground-based fiber-optic networks and the other over ground-to-satellite free-space links. A practical and versatile interferometric scheme is designed and demonstrated, which allows constructing highly non-degenerate sources with only conventional polarization optics. A method of directly producing entangled photon-pairs from optical fibers without interferometers is studied with thorough numerical analysis to show feasibility of experimental demonstration. An entangled photon source for the QEYSSat mission is conceptually designed, and several key parameters to fulfill a set of performance requirements are theoretically studied and experimentally verified. Secondly, this thesis presents two characterization platforms for optical components that are designed and implemented for the QEYSSat mission. One is to precisely measure transmitted wavefronts of large optics including telescopes. A proof-of-principle experiment is conducted with accurate modelling of measurement apparatus via three-dimensional raytracing, and quantitative agreement between the experiment and simulations validates our methodology. The other provides polarization characterizations for a variety of optical components including lenses, mirrors, and telescopes with consistent precision. A detailed description of subsystems including calibrations and test procedures is provided. Polarization-test results of several components for the QEYSSat are discussed. Third, quantum frequency transducers are developed for single-photon quantum key distributions with QEYSSat links. The devices are designed to translate the wavelength of single-photons emitted from quantum dot single-photon sources to QEYSSat channel wavelength via four-wave mixing Bragg-scattering process. Two optical media are concerned: a silicon nitride ring resonator and a photonic crystal fiber. Thorough numerical simulations are performed to estimate the device performance for both cases. A proof-of-principle demonstration of the frequency translation is conducted with a commercial photonic crystal fiber. Finally, a quantum simulator, serving as a quantum node in satellite-assisted quantum networks, is designed in a silicon nitride nanophotonic platform with cesium atoms. The designed photonic structure tailors electromagnetic vacuum such that photon-mediated forces between atoms causes collective motions mediating site-selective SU(2) spin-spin interactions. A coherent spin-exchange rate between atoms and collective dissipation rate of atoms are precisely estimated via finite-element time domain simulations. Furthermore, two schemes of trapping atoms in the vicinity of the designed structure are studied with calculations of potential energies and phonon tunneling rates. Experimental progress toward realization of the proposed system is summarized. The presented research activities of designing, analyzing, and implementing devices demonstrates the readiness of satellite-assisted quantum networks. This work contributes to creating quantum channels by entanglements with interfaces of various quantum systems in line with a broader scope of establishing a global quantum internet and quantum space exploration

The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Final Report

The Habitable Exoplanet Observatory, or HabEx, has been designed to be the Great Observatory of the 2030s. For the first time in human history, technologies have matured sufficiently to enable an affordable space-based telescope mission capable of discovering and characterizing Earthlike planets orbiting nearby bright sunlike stars in order to search for signs of habitability and biosignatures. Such a mission can also be equipped with instrumentation that will enable broad and exciting general astrophysics and planetary science not possible from current or planned facilities. HabEx is a space telescope with unique imaging and multi-object spectroscopic capabilities at wavelengths ranging from ultraviolet (UV) to near-IR. These capabilities allow for a broad suite of compelling science that cuts across the entire NASA astrophysics portfolio. HabEx has three primary science goals: (1) Seek out nearby worlds and explore their habitability; (2) Map out nearby planetary systems and understand the diversity of the worlds they contain; (3) Enable new explorations of astrophysical systems from our own solar system to external galaxies by extending our reach in the UV through near-IR. This Great Observatory science will be selected through a competed GO program, and will account for about 50% of the HabEx primary mission. The preferred HabEx architecture is a 4m, monolithic, off-axis telescope that is diffraction-limited at 0.4 microns and is in an L2 orbit. HabEx employs two starlight suppression systems: a coronagraph and a starshade, each with their own dedicated instrument

The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Final Report

The Habitable Exoplanet Observatory, or HabEx, has been designed to be the Great Observatory of the 2030s. For the first time in human history, technologies have matured sufficiently to enable an affordable space-based telescope mission capable of discovering and characterizing Earthlike planets orbiting nearby bright sunlike stars in order to search for signs of habitability and biosignatures. Such a mission can also be equipped with instrumentation that will enable broad and exciting general astrophysics and planetary science not possible from current or planned facilities. HabEx is a space telescope with unique imaging and multi-object spectroscopic capabilities at wavelengths ranging from ultraviolet (UV) to near-IR. These capabilities allow for a broad suite of compelling science that cuts across the entire NASA astrophysics portfolio. HabEx has three primary science goals: (1) Seek out nearby worlds and explore their habitability; (2) Map out nearby planetary systems and understand the diversity of the worlds they contain; (3) Enable new explorations of astrophysical systems from our own solar system to external galaxies by extending our reach in the UV through near-IR. This Great Observatory science will be selected through a competed GO program, and will account for about 50% of the HabEx primary mission. The preferred HabEx architecture is a 4m, monolithic, off-axis telescope that is diffraction-limited at 0.4 microns and is in an L2 orbit. HabEx employs two starlight suppression systems: a coronagraph and a starshade, each with their own dedicated instrument.Comment: Full report: 498 pages. Executive Summary: 14 pages. More information about HabEx can be found here: https://www.jpl.nasa.gov/habex

NASA Compendium of Satellite Communications Programs

A comprehensive review is presented of worldwide communication programs that range in time from the inception of satellite communications to August 1971. The programs included are: Echo, Courier, West Ford, Telstar, Relay, Syncom, Lincoln experimental satellites, Intelsat, Tacsat, Skynet, Nato system, and Telesat