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This paper describe a millimeter wave low noise amplifier with extraordinary low noise, low consumption, and wide frequency range. These results are achieved utilizing state-of-the-art InP HEMT transistors coupled with CPW circuit design. The paper describes the transistor models, modeled and measured on-wafer and in-module results at both 300K am 24K operating temperatures for many samples of the device.
We investigate the possibility of using InGaAs-AlAsSb-InP coupled quantum wells to generate THz radiation by means of intersubband optical pumping. We show that large conduction band offsets of these quantum wells make it possible to use conventional near-infrared diode lasers around 1.55 micron as pump sources. Taking into account the pump-probe coherent interaction and the optical nonlinearity for the pump field, we calculate the THz gain of the quantum well structure. We show that resonant Raman scattering enhances the THz gain at low and moderate optical pumping levels. When the pump intensity is strong, the THz gain is reduced by pump-induced population redistribution and pump-probe coherent interactions.
InAs self-organized quantum dots have been grown in InGaAs quantum well on InP substrates by metalorganic vapor phase epitaxy. Atomic Force Microscopy confirmed of quantum dot formation with dot density of 3X10(sup 10) cm(sup -2). Improved dot size uniformity and strong room temperature photoluminescence up to 2 micron were observed after modifying the InGaAs well.
Single-stack InAsSb self-assembled quantum-dot lasers based on (001) InP substrate have been grown by metalorganic vapor-phase epitaxy. The narrow ridge waveguide lasers lased at wavelengths near 2 mu m up to 25 degrees C in continuous-wave operation. At room temperature, a differential quantum efficiency of 13 percent is obtained and the maximum output optical power reaches 3 mW per facet with a threshold current density of 730 A/cm(sup 2). With increasing temperature the emission wavelength is extremely temperature stable, and a very low wavelength temperature sensitivity of 0.05 nm/degrees C is measured, which is even lower than that caused by the refractive index change.
Single-stack InAs self-assembled quantum dots (QD) lasers based on InP substrate have been grown by metalorganic vapor phase epitaxy. The narrow ridge waveguide lasers lased up to 260 K in continuous wave operation, and near room temperature in pulsed mode, with wavelengths between 1.59 to 1.74 mu m.
In this paper, we present two single stage MMIC amplifiers with the first demonstrating a measured S21 gain of 3-dB at 280-GHz and the second demonstrating 2.5-dB gain at 300- GHz, which is the threshold of the sub-millimeter wave regime. The high-frequency operation is enabled by a high-speed InP HEMT with a 35-nm gate. This is the first demonstrated S21 gain at sub-millimeter wave frequencies in a MMIC.
A monolithic micro - wave integrated-circuit (MMIC) singlestage amplifier containing an InP-based high-electron-mobility transistor (HEMT) plus coplanar-waveguide (CPW) transmission lines for impedance matching and input and output coupling, all in a highly miniaturized layout as needed for high performance at operating frequencies of hundreds of gigahertz is described.
This paper discusses the applicability of hybrid CMOS/InP-MMIC mm-Wave systems to remote sensing instrumentation for space exploration in Earth and Planetary science. We review the need for lower power and lighter weight instruments to accommodate the limited payload resources of exploration spacecraft, and then demonstrate how hybrid systems can address these challenges. An example hybrid CMOS-InP radiometer operating at 100 GHz is discoursed in detail including circuit & system design, interfacing and packaging techniques. Measurements are presented showing that the hybrid approach does not compromise instrument sensitivity.
We will present a Monolithic Millimeter-wave Integrated Circuit (MMIC) chip set which provides high output-power sources for driving diode frequency multipliers into the terahertz range. The chip set was fabricated at HRL Laboratories using a 0.l-μm gatelength InAI/InGaAs/InP high electron mobility transistor (HEMT) process, and features transistors with an fmax above 600 GHz. The HRL InP HEMT process has already demonstrated amplifiers in the 60-200 GHz range. In this paper, these high frequency HEMTs form the basis for power sources up to 170 GHz.
Single-stack InAsSb self-assembled quantum-dot lasers based on (001) InP substrate have been grown by metalorganic vapor-phase epitaxy.
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°.
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This paper presents some recently developed MMICs based on a 0.1 meu gate-length InAlAs/InGaAs/InP HEMT process with an fmax above 600 GHz.