ORCID Profile
0000-0003-0729-5617
Current Organisation
University of California, Irvine
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Publisher: American Chemical Society (ACS)
Date: 09-11-2022
Publisher: AIP Publishing
Date: 25-12-2017
DOI: 10.1063/1.5008445
Abstract: Nonlinear optical waveguides enable the integration of entangled photon sources and quantum logic gates on a quantum photonic chip. One of the major challenges in such systems is separating the generated entangled photons from the pump laser light. In this work, we experimentally characterize double-N-shaped nonlinear optical adiabatic couplers designed for the generation of spatially entangled photon pairs through spontaneous parametric down-conversion, while simultaneously providing spatial pump filtering and keeping photon-pair states pure. We observe that the pump photons at a wavelength of 671 nm mostly remain in the central waveguide, achieving a filtering ratio of over 20 dB at the outer waveguides. We also perform classical characterization at the photon-pair wavelength of 1342 nm and observe that light fully couples from an input central waveguide to the outer waveguides, showing on chip separation of the pump and the photon-pair wavelength.
Publisher: American Physical Society (APS)
Date: 22-11-2011
Publisher: OSA
Date: 2015
Publisher: OSA
Date: 2015
Publisher: The Optical Society
Date: 13-11-2017
DOI: 10.1364/OL.42.004724
Publisher: American Chemical Society (ACS)
Date: 11-12-2021
Publisher: OSA
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 26-07-2011
Publisher: IEEE
Date: 05-2011
Publisher: The Optical Society
Date: 11-2011
DOI: 10.1364/OE.19.023188
Publisher: Optica Publishing Group
Date: 22-06-2020
DOI: 10.1364/OE.392536
Abstract: We present a planar spectro-polarimeter based on Fabry-Pérot cavities with embedded polarization-sensitive high-index nanostructures. A 7 µm-thick spectro-polarimetric system for 3 spectral bands and 2 linear polarization states is experimentally demonstrated. Furthermore, an optimal design is theoretically proposed, estimating that a system with a bandwidth of 127 nm and a spectral resolution of 1 nm is able to reconstruct the first three Stokes parameters with a signal-to-noise ratio of -13.14 dB with respect to the the shot noise limited SNR. The pixelated spectro-polarimetric system can be directly integrated on a sensor, thus enabling applicability in a variety of miniaturized optical devices, including but not limited to satellites for Earth observation.
Publisher: American Physical Society (APS)
Date: 31-03-2014
Publisher: Wiley
Date: 26-11-2015
Publisher: Wiley
Date: 10-10-2022
Abstract: Nanoresonators fabricated from low‐loss dielectrics with second‐order nonlinearity have emerged as a widespread platform for nonlinear frequency conversion at the nanoscale. However, a persisting challenge in this research is the generated complex far‐field polarization state of the upconverted light, which is a limiting factor in many applications. It will be highly desirable to generate uniform far‐field polarization states across all propagation directions, to control the polarization truly along the optical axis and to simultaneously be able to tune the polarization along the entire circumference of the Poincaré sphere by solely modifying the excitation polarization. Here, a nonlinear nanoresonator combining all these properties is theoretically proposed and experimentally demonstrated. At first, an analytical model connecting the induced multipolar content of a nanoresonator with a desired far‐field polarization is derived. Based on this, a nonlinear dielectric nanoresonator is designed to enable sum‐frequency generation (SFG) with highly pure and tuneable far‐field polarization states. In the experiment, the nanoresonators fabricated from the III‐V semiconductor gallium arsenide in (110)‐orientation are excited in an SFG scheme with in idually controllable excitation beams. The generation of highly uniform and tuneable far‐field polarization states is demonstrated by combining back‐focal plane measurements with Stokes polarimetry.
Publisher: The Optical Society
Date: 13-11-2009
DOI: 10.1364/OL.34.003589
Publisher: American Chemical Society (ACS)
Date: 14-03-2018
Publisher: American Physical Society (APS)
Date: 13-12-2021
Publisher: IOP Publishing
Date: 09-07-2019
Publisher: IEEE
Date: 08-2011
Publisher: American Chemical Society (ACS)
Date: 15-12-2021
Publisher: OSA
Date: 2016
Publisher: The Optical Society
Date: 30-11-2016
DOI: 10.1364/OL.41.005604
Publisher: American Physical Society (APS)
Date: 12-2010
Publisher: American Chemical Society (ACS)
Date: 10-05-2021
Publisher: AIP Publishing
Date: 02-2018
DOI: 10.1063/1.5009766
Abstract: Spontaneous parametric down-conversion (SPDC) spectroscopy using photon pairs is a promising avenue towards affordable mid-infrared (MIR) spectroscopy. Here, we experimentally investigate the feasibility of using periodically poled waveguides in lithium niobate for SPDC spectroscopy applications. We find the waveguides suitable to generate wavelength non-degenerate photon pairs with one photon in the MIR spectral range with high fluence. We use this to determine the cutoff wavelengths of the waveguide mode in the MIR by performing only measurements in the near-infrared spectral range.
Publisher: American Chemical Society (ACS)
Date: 12-11-2020
Publisher: American Chemical Society (ACS)
Date: 15-08-2016
DOI: 10.1021/ACS.NANOLETT.6B01816
Abstract: Nonlinear optical phenomena in nanostructured materials have been challenging our perceptions of nonlinear optical processes that have been explored since the invention of lasers. For ex le, the ability to control optical field confinement, enhancement, and scattering almost independently allows nonlinear frequency conversion efficiencies to be enhanced by many orders of magnitude compared to bulk materials. Also, the subwavelength length scale renders phase matching issues irrelevant. Compared with plasmonic nanostructures, dielectric resonator metamaterials show great promise for enhanced nonlinear optical processes due to their larger mode volumes. Here, we present, for the first time, resonantly enhanced second-harmonic generation (SHG) using gallium arsenide (GaAs) based dielectric metasurfaces. Using arrays of cylindrical resonators we observe SHG enhancement factors as large as 10(4) relative to unpatterned GaAs. At the magnetic dipole resonance, we measure an absolute nonlinear conversion efficiency of ∼2 × 10(-5) with ∼3.4 GW/cm(2) pump intensity. The polarization properties of the SHG reveal that both bulk and surface nonlinearities play important roles in the observed nonlinear process.
Publisher: Elsevier BV
Date: 12-2020
Publisher: The Optical Society
Date: 25-01-2022
DOI: 10.1364/OE.27.001632
Publisher: Optica Publishing Group
Date: 30-06-2022
DOI: 10.1364/PRJ.450410
Abstract: We propose a novel quantum nonlinear interferometer design that incorporates a passive parity–time (PT)-symmetric coupler sandwiched between two nonlinear sections where signal–idler photon pairs are generated. The PT symmetry enables efficient coupling of the longer-wavelength idler photons and facilitates the sensing of losses in the second waveguide exposed to analyte under investigation, whose absorption can be inferred by measuring only the signal intensity at a shorter wavelength where efficient detectors are readily available. Remarkably, we identify a new phenomenon of sharp signal intensity fringe shift at critical idler loss values, which is distinct from the previously studied PT symmetry breaking. We discuss how such unconventional properties arising from quantum interference can provide a route to enhancing the sensing of analytes and facilitate broadband spectroscopy applications in integrated photonic platforms.
Publisher: American Chemical Society (ACS)
Date: 05-03-2019
Publisher: IEEE
Date: 05-2011
Publisher: American Association for the Advancement of Science (AAAS)
Date: 07-07-2017
Abstract: We show directional light routing and high–bit rate data transmission using a nanoantenna integrated on a low-loss waveguide.
Publisher: American Physical Society (APS)
Date: 14-07-2014
Publisher: OSA
Date: 2018
Publisher: American Chemical Society (ACS)
Date: 08-04-2015
DOI: 10.1021/ACS.NANOLETT.5B00560
Abstract: Here we suggest and realize an ultracompact plasmonic spectral-band demultiplexer for telecommunication wavelengths integrated onto an optical waveguide that couples two wavelength-encoded optical signals in the O- and the C-band in opposite directions of a silicon waveguide. In this way, we demonstrate a plasmonic key element for on-chip optical data processing that can also be used as a functional link between on- and off-chip optical signals.
No related grants have been discovered for Yama Akbari.