A5055825135- Superconducting and THz Device Technology
- Physics of Superconductivity and Magnetism
- Microwave Engineering and Waveguides
- Radio Frequency Integrated Circuit Design
- Thermal Radiation and Cooling Technologies
- Terahertz technology and applications
- Photonic and Optical Devices
- Superconductivity in MgB2 and Alloys
- Radio Astronomy Observations and Technology
- Advanced Thermodynamic Systems and Engines
- Gyrotron and Vacuum Electronics Research
- Antenna Design and Optimization
- Atmospheric Ozone and Climate
- Antenna Design and Analysis
- Particle accelerators and beam dynamics
- Semiconductor Quantum Structures and Devices
- Advanced Antenna and Metasurface Technologies
- Advanced Semiconductor Detectors and Materials
- Spacecraft and Cryogenic Technologies
- Advanced Thermodynamics and Statistical Mechanics
- Radiation Detection and Scintillator Technologies
- Calibration and Measurement Techniques
- Quantum and electron transport phenomena
- Spacecraft Design and Technology
- Soil Moisture and Remote Sensing
California Institute of Technology
1998-2022
Jet Propulsion Laboratory
2008-2020
Space Micro (United States)
1995-2002
Space Research Organisation Netherlands
1989-1993
Chalmers University of Technology
1987-1988
We show experimentally that a high-resolution imaging radar operating at 576-605 GHz is capable of detecting weapons concealed by clothing standoff ranges 4-25 m. also demonstrate the critical advantage 3-D image reconstruction for visualizing hidden objects using active-illumination coherent terahertz imaging. The present system can torso with <1 cm resolution 4 m in about five minutes. Greater distances and much higher frame rates should be achievable capitalizing on bandwidth, output...
We have developed a high-resolution imaging radar at 580 GHz. Coherent illumination in the 576-589 GHz range and phase-sensitive detection are implemented an all-solid-state design based on Schottky diode sensors sources. By employing frequency-modulated continuous wave (FMCW) technique, we achieve centimeter-scale resolution while utilizing fractional bandwidths of less than 3%. Our high operating frequencies also permit cross-range several-meter standoff distances without large apertures....
We report on the development of a 0.25-μm InP HBT IC technology for lower end THz frequency band (0.3-3 THz). Transistors demonstrate an extrapolated f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> >;800 GHz while maintaining common-emitter breakdown voltage (BVCEO) >;4 V. The transistors have been integrated in full process that includes three-levels interconnects, and backside processing. has utilized key circuit building blocks...
We introduce a novel antenna concept suitable for future integrated arrays at terahertz frequencies. The consists of an extended hemispherical lens fed by leaky wave waveguide feed that can be with sensors and detectors such as Schottky diodes. In this architecture, couple TE/TM modes are excited in resonant cavity formed opening ground plane silicon lens. Due to these modes, the field radiated inside is very directive pattern illuminates upper part Having primary helps increase f-number...
We report on the development of a 0.25 μm InP HBT technology suitable for integrated circuit demonstrations at lower end THz frequency band (0.3-3THz). Transistors demonstrate an extrapolated f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> >800 GHz while maintaining common-emitter breakdown voltage (BV xmlns:xlink="http://www.w3.org/1999/xlink">CEO</sub> ) >4 V. The transistors have been in full IC process that includes three-levels...
Two indium-phosphide (InP) double-heterojunction bipolar transistor (DHBT) based terahertz monolithic integrated circuit (TMIC) amplifiers are reported with record operating bandwidths up to 694 GHz. The first amplifier uses 3 μm long emitter transistors, has 24 dB gain at 670 GHz, and a saturated output power of -4 dBm 585 second 6 20 655 -0.7 Both TMICs use Teledyne's 130nm InP DHBT transistors in common base configuration matched using inverted CPW transmission lines realized...
Mixing experiments have been performed at frequencies from 4 to 20 GHz on Nb thin-film superconducting hot-electron bolometers varying in length 0.08 3 μm. The intermediate frequency (IF) bandwidth is found vary as L−2, with L the bridge length, for devices shorter than √12 Le−ph≊1 μm, Le−ph electron-phonon length. shortest device has an IF greater 6 GHz, largest reported a low-Tc bolometric mixer. conversion efficiencies range −5 −11 dB (single sideband, SSB). For short bridges, mixer noise...
Heterodyne measurements have been made at 533 GHz using a novel superconducting hot-electron bolometer in waveguide mixer. The is 0.3 μm long niobium microbridge with transition temperature of 5 K. short length ensures that electron diffusion dominates over electron-phonon interactions as the cooling mechanism, which should allow heterodyne detection intermediate frequencies (if) several GHz. A Y-factor response 1.15 dB has obtained an if 1.4 77 and 295 K loads, indicating receiver noise 650...
We report the first submillimeter-wave imaging system that has radar ranging capabilities. By frequency-modulating K-band synthesizers of a single-pixel 630 GHz scanning vector imager and applying distortion compensation technique in software, we have achieved range resolution approximately 2 cm for targets at several meters. Relief images test objects obtained with our demonstrate three-dimensional THz scanned is feasible using room temperature, all solid-state approach.
We report a 600 GHz amplifier with > 30 dB peak gain, based on 12 cascaded differential common-base (CB) stages, in 130 nm InP HBT process. Three consecutive CB stages are grouped as unit gain block, sharing common bias current. Each stage is stabilized by cross-coupled capacitive feedback. Output powers from two branches combined through 4-way combiner, resulting 4× increase power compared to single single-ended output stage. On-wafer testing WR-1.5 band (500-750 GHz) shows that the...
Abstract We describe a planar antenna structure consisting of two half‐wave dipoles, which are backed by metallic reflector to create an image more elements. The array produces rather wide main beam, and is therefore used with dielectric lens. far‐field pattern the dipole liens has cross‐pol better than −20 dB, side lobes below −13 dB over octave band. impedance at feedpoint approximately 70 ‐ j10 Ω center
The Stratospheric TeraHertz Observatory (STO) is a NASA funded, Long Duration Balloon (LDB) experiment designed to address key problem in modern astrophysics: understanding the Life Cycle of Interstellar Medium (ISM). STO will survey section Galactic plane dominant interstellar cooling line [C II] (1.9 THz) and important star formation tracer [N (1.46 at ~1 arc minute angular resolution, sufficient spatially resolve atomic, ionic molecular clouds 10 kpc. itself has three main components; 1)...
We present a 630 GHz transmitter IC based on 210 PLL and 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> -order sub-harmonic transmit mixer in an 130nm InP HBT process. The output can be tuned across 15 with −51 dBc −74 of phase noise at 100 Hz 10 KHz offset, respectively. Measured saturated RF power was −30 to −33 dBm, while consuming 650 mW. occupies 1.37 mm xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . To the authors'...
We report a systematic, comprehensive set of measurements on the dynamics and noise processes in diffusion phonon-cooled superconducting hot-electron bolometer mixers which will serve as ultralow detectors THz heterodyne receivers. The conversion efficiency output devices varying lengths were measured with radio frequency between 8 40 GHz. studied consist 100-Å-thin film Nb bridges connected to thick (1000 Å), high conductivity normal metal (Au) leads. range from 0.08 3 μm. For longer than...
We present the hardware and experimental results from a 600 GHz imaging radar with sub-centimeter resolution in all three spatial dimensions. The FMCW transceiver is built on back-end of commercial microwave components - front-end custom designed frequency multipliers mixers. optics consists 40 cm diameter ellipsoidal primary reflector 4 m focal length. acquired images will be compared those achieved more traditional sub-millimeter wave active technique.
Summary form only given. Extended Interaction Klystrons have been demonstrated at frequencies up to 218 GHz CW and 229 pulsed. Modern design, fabrication, measurement technologies show promise of extending their operation into the THz regime. This paper describes challenges some novel approaches development EIKs operating terahertz frequencies, while simultaneously meeting demanding requirements for output power, gain, bandwidth, efficiency.The main in design include focus transport an...
This paper describes heterodyne measurements at 533 GHz using a novel superconducting hot electron bolometer in waveguide mixer block. The is thin (10 nm) and narrow (0.1 /spl mu/m) strip of niobium with length less than half micron critical temperature approximately 5.5 K. short ensures that diffusion dominates over electron-phonon interaction as cooling mechanism for the electrons, thus allowing detection intermediate frequencies several GHz. A Y-factor response 1.15 dB has been obtained...
We report on a low noise waveguide-based heterodyne mixer utilizing superconductiang NbN hot electron bolometer (HEB) operating near 2.7 THz. The is an nano-bridge integrated with gold bowtie planar antenna ultra-thin silicon substrate of ~ 2-3 μm thickness. To produce the waveguide embedding circuit for use at such high frequency, we adopted novel approach combining UV-lithography and micro-plating techniques. response agreed precisely model predictions, measured minimum uncorrected DSB...
A terahertz differential eight-stage amplifier fabricated using state-of-the-art 125 nm double-heterojunction bipolar transistors (DHBT) is presented. The four-port unit-cell chain designed for optimum forward gain with no even and odd-mode reverse gains. Unbalanced single-ended feed networks are added to preserve the without inducing oscillations. proposed scheme validated by a stable operation in 325-to-450 GHz range peak of 22 dB at 375 GHz.
We report receiver noise temperature measurements using a quasioptically coupled diffusion-cooled hot-electron bolometer mixer at local oscillator frequency of 1267 GHz, and an intermediate 1.4 GHz. A best double-sideband (DSB) 1880 K was measured, with estimated 945 (DSB), conversion efficiency including coupling losses -19 dB (DSB). The power requirement for this device is roughly 6 nW. less than twice that measured earlier in waveguide 530 which shows the sensitivity type does not degrade...
Extended Interaction Klystrons have been demonstrated at frequencies up to 218 GHz CW and 229 pulsed. Modern design, fabrication, measurement technologies show promise of extending their operation into the THz regime. This paper describes challenges some novel approaches development EIKs operating 670, 850 1030 GHz, while simultaneously meeting demanding requirements for output power, gain, bandwidth, efficiency.
This letter presents a 529 GHz 2:1 dynamic frequency divider in 130 nm InP HBT process, which, to the best of authors’ knowledge, is fastest reported thus far. The presented based on novel structure overcome bandwidth limitations traditional design. On-wafer measurement shows that operates with input from 528.0 529.2 bias voltage tuning, while consuming PDC ≤ 196 mW. A driver amplifier, integrated for testing purpose, dissipates 348 mW dc power.
Diffusion-cooled aluminum hot-electron bolometer (HEB) mixers are of interest for low-noise high resolution THz-frequency spectroscopy within astrophysics. Al HEB offer operation with an order magnitude less local oscillator power, higher intermediate frequency bandwidth and potentially lower noise than competing devices made from other materials. We report on mixer experiments at 618 GHz fabricated films sheet resistances in the range about 55 /spl Omega/ down to 9 per square. Intermediate...