Results 1 to 10 of about 9,836,724 (331)
Wideband Phase-Gradient Metasurface Antenna With Focused Beams
IEEE Access, 2019 A transmitting lens antenna with focused beams by employing four-layer phase-gradient metasurface (PGMS) is proposed. A wideband slot-coupled antenna is mounted close to the focal position of the PGMS acting as a feed.
Jia-Jun Liang +4 more
doaj +2 more sources
Extracting the differential phase in dual atom interferometers by modulating magnetic fields
, 2016 We present a new scheme for measuring the differential phase in dual atom interferometers. The magnetic field is modulated in one interferometer, and the differential phase can be extracted without measuring the amplitude of the magnetic field by ...
Chen, Xi +8 more
core +1 more source
Low-complexity implementation of convex optimization-based phase retrieval
, 2018 Phase retrieval has important applications in optical imaging, communications and sensing. Lifting the dimensionality of the problem allows phase retrieval to be approximated as a convex optimization problem in a higher-dimensional space.
Arik, Sercan O., Kahn, Joseph M.
core +1 more source
Scintillation modeling with random phase gradient screens
Journal of Space Weather and Space ClimateMultiple studies of scintillation phenomena have shown that, in certain situations, the intense phase fluctuations of trans-ionospheric radio signals are associated with the scattering on strong electron density gradients.
Vasylyev Dmytro +8 more
doaj +1 more source
Phase Extraction Algorithm Based on the Spatial Carrier-Frequency Phase-Shifting Gradient
IEEE Photonics Journal, 2019 For improving the accuracy and processing speed of phase extraction, a new phase extraction algorithm based on the spatial carrier-frequency phase-shifting gradient (SCFPS-G) is proposed.
Haoren Zou +6 more
doaj +1 more source
Self-organization in He4 near the superfluid transition in heat flow and gravity
, 2010 We investigate the nonlinear dynamics of He4 slightly below the superffluid transition by integrating model F equations in three dimensions. When heated from above under gravity, a vortex tangle and a sheetlike phase slip are generated near the bottom ...
A. Onuki +8 more
core +1 more source
A practical density functional for polydisperse polymers
, 2001 The Flory Huggins equation of state for monodisperse polymers can be turned into a density functional by adding a square gradient term, with a coefficient fixed by appeal to RPA (random phase approximation). We present instead a model nonlocal functional
+8 more
core +1 more source
Direct measurement of quantum phase gradients in superfluid 4He flow
, 2007 We report a new kind of experiment in which we generate a known superfluid velocity in a straight tube and directly determine the phase difference across the tube's ends using a superfluid matter wave interferometer. By so doing, we quantitatively verify
Aditya Joshi +11 more
core +1 more source
Time-Varying Metasurfaces and Lorentz Non-Reciprocity
, 2015 A cornerstone equation of optics, Snell's law, relates the angles of incidence and refraction for light passing through an interface between two media.
Kildishev, Alexander +2 more
core +1 more source
Communication: Analytic gradients in the random-phase approximation
The Journal of Chemical Physics, 2013 The relationship between the random-phase-approximation (RPA) correlation energy and the continuous algebraic Riccati equation is examined and the importance of a stabilizing solution is emphasized. The criterion to distinguish this from non-stabilizing solutions can be used to ensure that physical, smooth potential energy surfaces are obtained.
Rekkedal, J +5 more
openaire +4 more sources