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This is the AmeriFlux version of the carbon flux data for the site US-INp INFLUX - Agricultural Site West of Indianapolis (Site-14b) . Site Description - Agricultural site
We present retrievals of tropospheric and stratospheric height profiles of particle mass, volume, surface area, and number concentrations in the case of wildfire smoke layers as well as estimates of smoke-related cloud condensation nuclei (CCN) and ice-nucleating particle (INP) concentrations from backscatter lidar measurements on the ground and in space. Conversion factors used to convert the optical measurements into microphysical properties play a central role in the data analysis, in addition to estimates of the smoke extinction-to-backscatter ratios required to obtain smoke extinction coefficients. The set of needed conversion parameters for wildfire smoke is derived from AERONET observations of major smoke events, e.g., in western Canada in August 2017, California in September 2020, and southeastern Australia in January–February 2020 as well as from AERONET long-term observations of smoke in the Amazon region, southern Africa, and Southeast Asia. The new smoke analysis scheme is applied to CALIPSO observations of tropospheric smoke plumes over the United States in September 2020 and to ground-based lidar observation in Punta Arenas, in southern Chile, in aged Australian smoke layers in the stratosphere in January 2020. These case studies show the potential of spaceborne and ground-based lidars to document large-scale and long-lasting wildfire smoke events in detail and thus to provide valuable information for climate, cloud, and air chemistry modeling efforts performed to investigate the role of wildfire smoke in the atmospheric system.
Nanowire arrays present many unique advantages for solar-to-chemical energy conversion. One possible advantage is that photon recycling between neighboring nanowires has the potential to increase solar energy conversion efficiencies. Here, in this work, we explore three underlying mechanisms of optical and electronic coupling between neighboring nanowires─incident photon scattering, photon recycling, and charge-carrier transport from the photoexcited nanowire to the neighboring nanowire via the underlying substrate─using single nanowire-level microscopy and spectroscopy measurements. We present a comprehensive analysis of light absorption and emission of a single nanowire at open circuit, and subsequent re-absorption and re-emission by a neighboring nanowire. We developed a novel correlated single nanowire microspectroscopy and widefield imaging methodology to spatially resolve photon communication pathways between neighboring nanowires and selectively image re-emitted and reflected photons. We developed unique multiphysics models to couple wave optics and semiconductor photophysics to especially isolate contributions from photon recycling and electronic transport to photon emission from neighboring nanowires. By systematically varying the morphologies of the nanowires modeled, we identified pathways to maximize photon recycling between neighboring nanowires. We concluded that the measured photoluminescence is more strongly influenced by the diffusion of charge carriers as compared to photon recycling in materials with moderate-to-large charge-carrier mobilities (>10 cm 2 V –1 s –1 ), and that photon recycling dictates photoluminescence intensity only when the charge-carrier mobility is low (<1 cm 2 V –1 s –1 ). The experimental and simulation platforms developed herein for photon management strategies can be leveraged by the semiconductor photocatalysis community to enhance solar-to-chemical conversion efficiencies in semiconductor nanowire arrays.
InPO4(H2O)2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. In3+ is bonded to six O2- atoms to form InO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of In–O bond distances ranging from 2.15–2.26 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent InO6 octahedra. The corner-sharing octahedra tilt angles range from 47–48°. There is one shorter (1.55 Å) and three longer (1.56 Å) P–O bond length. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.61 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one In3+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one In3+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one In3+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one In3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one In3+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one In3+, one P5+, and one H1+ atom.
InPO4(H2O)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. In3+ is bonded to six O2- atoms to form InO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of In–O bond distances ranging from 2.15–2.20 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent InO6 octahedra. The corner-sharing octahedra tilt angles range from 40–46°. There is one shorter (1.55 Å) and three longer (1.56 Å) P–O bond length. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.65 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a distorted bent 150 degrees geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.61 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one In3+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one In3+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one In3+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one In3+, one P5+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one In3+, one P5+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one In3+ and one P5+ atom.
CaIn2P2 crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two CaIn2P2 sheets oriented in the (0, 0, 1) direction. Ca2+ is bonded to six equivalent P3- atoms to form edge-sharing CaP6 octahedra. All Ca–P bond lengths are 2.97 Å. In2+ is bonded in a trigonal non-coplanar geometry to three equivalent P3- atoms. All In–P bond lengths are 2.63 Å. P3- is bonded to three equivalent Ca2+ and three equivalent In2+ atoms to form a mixture of edge and corner-sharing PCa3In3 octahedra. The corner-sharing octahedral tilt angles are 0°.
BaIn2P2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to six P3- atoms to form edge-sharing BaP6 octahedra. There are a spread of Ba–P bond distances ranging from 3.22–3.33 Å. In the second Ba2+ site, Ba2+ is bonded to six P3- atoms to form edge-sharing BaP6 octahedra. There are a spread of Ba–P bond distances ranging from 3.20–3.49 Å. There are four inequivalent In2+ sites. In the first In2+ site, In2+ is bonded in a trigonal non-coplanar geometry to three equivalent P3- atoms. All In–P bond lengths are 2.67 Å. In the second In2+ site, In2+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are two shorter (2.65 Å) and one longer (2.68 Å) In–P bond lengths. In the third In2+ site, In2+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.64 Å) and two longer (2.69 Å) In–P bond lengths. In the fourth In2+ site, In2+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.67 Å) and two longer (2.68 Å) In–P bond lengths. There are four inequivalent P3- sites. In the first P3- site, P3- is bonded to three Ba2+ and three In2+ atoms to form a mixture of edge and corner-sharing PBa3In3 octahedra. The corner-sharing octahedra tilt angles range from 7–12°. In the second P3- site, P3- is bonded to three Ba2+ and three equivalent In2+ atoms to form a mixture of edge and corner-sharing PBa3In3 octahedra. The corner-sharing octahedra tilt angles range from 20–73°. In the third P3- site, P3- is bonded to three equivalent Ba2+ and three In2+ atoms to form a mixture of edge and corner-sharing PBa3In3 octahedra. The corner-sharing octahedra tilt angles range from 7–73°. In the fourth P3- site, P3- is bonded to three equivalent Ba2+ and three In2+ atoms to form a mixture of edge and corner-sharing PBa3In3 octahedra. The corner-sharing octahedra tilt angles range from 12–66°.
SrIn2P2 crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two SrIn2P2 sheets oriented in the (0, 0, 1) direction. Sr2+ is bonded to six equivalent P3- atoms to form edge-sharing SrP6 octahedra. All Sr–P bond lengths are 3.09 Å. In2+ is bonded in a trigonal non-coplanar geometry to three equivalent P3- atoms. All In–P bond lengths are 2.66 Å. P3- is bonded to three equivalent Sr2+ and three equivalent In2+ atoms to form a mixture of edge and corner-sharing PSr3In3 octahedra. The corner-sharing octahedral tilt angles are 0°.
Abstract Metallic nanocavity lasers provide important technological advancement toward even smaller integrable light sources. They give access to widely unexplored lasing physics in which the distinction between different operational regimes, like those of thermal or coherent light emission, becomes increasingly challenging upon approaching a device with a near‐perfect spontaneous‐emission coupling factor . In fact, quantum‐optical studies have to be employed to reveal a transition to coherent emission in the intensity fluctuation behavior of nanolasers when the input–output characteristic appears thresholdless for nanolasers. Here, a new indicator for lasing operation in high‐ lasers is identified by showing that stimulated emission can give rise to a lineshape anomaly manifested as a transition from a Lorentzian to a Gaussian component in the emission linewidth that dominates the spectrum above the lasing threshold.
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This work demonstrates a monolithic surface acoustic wave amplifier fabricated by state-of-the-art heterogenous integration of a III-V InGaAs-based epitaxial material stack and LiNbO 3 . We compare amplification of Raleigh-SAW and leaky-SAW modes on a on Y-cut, X-propagating delay line amplifier. Due to the superior properties of the materials employed, we observe a net terminal gain of 3dB for an LSAW overtone mode This platform enables further advances in active and non-reciprocal piezoelectric acoustic devices.
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