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Jeffrey Fagan, Henry Wladkowski, Julian Duarte, Shashank R. Nandyala, Joshua Walker, Subash Kattel, Jeffrey Blackburn, Jon Pikal, William D. Rice
Preparation techniques for producing films of individualized, solution dispersed nanoparticles (NPs) for optical spectroscopy are often technically challenging and tailored for a specific NP system. In this work, we present a rapid, easy, and economical
Qingbin Fan, Mingze Liu, Cheng Zhang, Wenqi Zhu, Yilin Wang, Peicheng Lin, Feng Yan, Lu Chen, Henri Lezec, Yanqing Lu, Amit Agrawal, Ting Xu
Exquisite polarization control using optical metasurfaces has attracted considerable attention thanks to their ability to manipulate multichannel independent wavefronts with subwavelength resolution. Here we present a new class of metasurface polarization
Edgar Perez, Gregory Moille, Xiyuan Lu, Daron Westly, Kartik Srinivasan
Direct laser writing (DLW) has recently been used to create versatile micro-optic structures that facilitate photonic-chip coupling, like free-form lenses, free-form mirrors, and photonic wirebonds. However, at the edges of photonic chips, the top-down/off
Qing Li, Gregory Moille, Hossein Taheri, Ali Adibi, Kartik Srinivasan
Coupled-mode theory has been widely used in optics and photonics design. Despite its popularity, several different formulations of coupled-mode theory exist in the literature and their applicable range is not entirely clear, in particular when it comes to
Silicon photonics lacks a second-order nonlinear optical (chi(2)) response in general because the typical constituent materials are centro-symmetric and lack inversion symmetry, which prohibits chi(2) nonlinear processes such as second harmonic generation
Whispering-gallery microcavities have been used to realize a variety of efficient parametric nonlinear optical processes through the enhanced light-matter interaction brought about by supporting multiple high quality factor and small modal volume
Nathan T. Ersumo, Cem Yalcin, Nick Antipa, Nicolas Pegard, Laura Waller, Omar D. Lopez, Rikky Muller
Dynamic axial focusing functionality has recently seen widespread incorporation in microscopy, augmented/virtual reality (AR/VR), adaptive optics, and material processing. Yet the limitations of existing varifocal tools continue to beset the performance
Wonil Nam, Yuming Zhao, Junyeob Song, Seied Ali Safiabadi Tali, Seju Kang, Wenqi Zhu, Henri Lezec, Amit Agrawal, Peter J. Vikesland, Wei Zhou
Ultrasensitive surface-enhanced Raman spectroscopy (SERS) still faces difficulties in quantitative analysis because of its susceptibility to local optical field variations at plasmonic hotspots in metallo-dielectric nanostructures. Current SERS calibration
Optical parametric oscillation (OPO) in a microresonator is promising as an efficient and scalable approach to on-chip coherent visible light generation. However, so far, only red light near the edge of the visible band at 710 nm has been reported. In this
Sara A. Alodan, Justin Gorham, Frank W. DelRio, Fadhel Alsaffar, Ghadeer Aljalham, Chongwu Zhou, Moh R. Amer
Newly explored two-dimensional (2D) materials have shown promising optical properties, owning to the tunable band gap of the layered material with its thickness. A widely used method to achieve tunable light emission (or photoluminescence) is through
Pengcheng Huo, Maowen Song, Wenqi Zhu, Cheng Zhang, Lu Chen, Henri Lezec, Yanqing Lu, Amit Agrawal, Ting Xu
We design and experimentally demonstrate a TiO2 metasurface that enables full-color generation and ultrasmooth color brightness variations. The reproduced famous artwork "girl with a pearl earring" features photorealistic color representation and
Wenqi Zhu, Shawn M. Divitt, Matthew S. Davis, Cheng Zhang, Ting Xu, Henri Lezec, Amit Agrawal
Recent advancements in the ability to design, fabricate and characterize optical and optoelectronic devices at the nanometer scale have led to tremendous developments in the miniaturization of optical systems and circuits. Development of wavelength scale
Robin P. Hansen, Amit K. Agrawal, Michael Shur, Jerry Tersoff, Babak Nikoobakht, Yuqin Zong
"Efficiency droop," i.e., a decline in brightness of light-emitting diodes (LEDs) at high electrical currents, limits the performance of all commercial LEDs and has limited the output power of submicrometer LEDs and lasers to nanowatts. We present a fin p
Si Zhang, Pengcheng Huo, Wenqi Zhu, Cheng Zhang, Peng Chen, Mingze Liu, Lu Chen, Henri Lezec, Amit Agrawal, Yanqing Lu, Ting Xu
Light beams carrying spin angular momentum (SAM) and orbital angular momentum (OAM) have created novel opportunities in the areas of optical communications, imaging, micromanipulation and quantum optics. However, complex optical setups are required to
Gregory T. Moille, Lin Chang, Weiqiang Xie, Ashutosh S. Rao, Xiyuan Lu, Marcelo I. Davanco, John E. Bowers, Kartik A. Srinivasan
We demonstrate stable microresonator Kerr solitons in a III-V platform through cryogenic quenching of the thermorefractive effect. Such phase-stable operation is critical to fully exploit the high nonlinearity and low loss available in this platform.
Dmitry Kurouski, Alexandre Dazzi, Renato Zenobi, Andrea Centrone
The advent of nanotechnology, and the need to understand the chemical composition at the nanoscale, has stimulated the convergence of IR and Raman spectroscopy with scanning probe methods, resulting in new nanospectroscopy paradigms. Here we review two of
Georg Ramer, Mohit Tuteja, Joseph R. Matson, Marcelo I. Davanco, Thomas G. Folland, Andrey Kretinin, Takashi Taniguchi, Kenji Watanabe, Kostya Novoselov, Joshua D. Caldwell, Andrea Centrone
The anisotropy of hexagonal boron nitride (hBN) crystals gives rise to hyperbolic phonon polaritons (HPhPs), notable for their volumetric frequency-dependent angular propagation and strong confinement. For frustum (truncated nanocone) structures, theory
Sonia M. Buckley, Alexander N. Tait, Galan Moody, Kevin L. Silverman, Sae Woo Nam, Richard P. Mirin, Jeffrey M. Shainline, Stephen Olson, Joshua Hermann, Satyvalu Papa Rao
W centers are trigonal defects generated by self-ion implantation in silicon that exhibit photoluminescence at 1.218\textmu m. We have shown previously that they can be used in waveguide-integrated all-silicon light-emitting diode sources. Here we optimize
Radislav A. Potyrailo, J. Brewer, B. Cheng, M. A. Carpenter, N. Houlihan, Andrei Kolmakov
Existing sensors for gaseous species often degrade their performance because of the loss of the measurement accuracy in the presence of interferences. Thus, new sensing approaches are required with improved sensor selectivity. We are developing a new
Qianhuan Yu, Junyi Gao, Nan Ye, Baiheng Chen, Keye Sun, Linli Xie, Kartik Srinivasan, Michael Zervas, Gabriele Navickaite, Michael Geiselmann, Andreas Beling
Heterogeneous integration through low-temperature die bonding is a promising technique to enable high-performance III-V photodetectors on the silicon nitride (Si3N4) photonic platform. Here we demonstrate InGaAs/InP modified uni-traveling carrier
Saeed Khan, Jeff Shainline, Richard Mirin, Sae Woo Nam, Sonia Buckley, Jeff Chiles
We demonstrate adiabatically tapered fibers terminating in sub-micron tips that are clad with a higher-index material for coupling to an on-chip waveguide. This cladding enables coupling to a high-index waveguide without losing light to the buried oxide. A
Matthew S. Davis, Wenqi Zhu, Jared Strait, Jay K. Lee, Henri Lezec, Steve Blair, Amit Agrawal
Manipulation of plasmon modes at ultraviolet wavelengths using engineered nanophotonic devices allows for the development of high-sensitivity chiroptical spectroscopy systems. We present here a framework for the fabrication and characterization of Al based