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SILICON-GERMANIUM HETEROJUNCTION BIPOLAR TRANSISTORS FOR LARGE-SCALE LOW-POWER CRYOGENIC SENSING SYSTEMS
Cryogenic low noise amplifiers (LNAs) are one of the key components in many emerging applications such as radio astronomy or quantum computing in which a weak incoming signal needs to be read out. There have been extensive studies on the feasibility of leveraging silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) to implement cryogenic LNAs in the past. The deployment of such LNAs in the future large-scale systems in radio astronomy or quantum computing is contingent upon the possibility of developing LNAs with reduced DC power dissipation to enable the cooling of a large number of array elements inside a cryogenic cooler. In this dissertation, we focus on the cryogenic operation of SiGe HBTs at reduced supply voltages for the implementation of ultra low- power LNAs and their applications for scalable receiver systems. In addition, the limitations of the SiGe HBT cryogenic models for the operation at high current densities are investigated for the implementation of modern high speed SiGe HBT circuits
An rf Quantum Capacitance Parametric Amplifier
We demonstrate a radio-frequency parametric amplifier that exploits the
gate-tunable quantum capacitance of an ultra high mobility two dimensional
electron gas (2DEG) in a GaAs heterostructure at cryogenic temperatures. The
prototype narrowband amplifier exhibits a gain greater than 20 dB up to an
input power of - 66 dBm (1 dB compression), and a noise temperature TN of 1.3 K
at 370 MHz. In contrast to superconducting amplifiers, the quantum capacitance
parametric amplifier (QCPA) is operable at tesla-scale magnetic fields and
temperatures ranging from milli kelvin to a few kelvin. These attributes,
together with its low power (microwatt) operation when compared to conventional
transistor amplifiers, suggest the QCPA may find utility in enabling on-chip
integrated readout circuits for semiconductor qubits or in the context of space
transceivers and radio astronomy instruments
125 - 211 GHz low noise MMIC amplifier design for radio astronomy
To achieve the low noise and wide bandwidth required for millimeter wavelength astronomy applications, superconductor-insulator-superconductor (SIS) mixer based receiver systems have typically been used. This paper investigates the performance of high electron mobility transistor (HEMT) based low noise amplifiers (LNAs) as an alternative approach for systems operating in the 125 — 211 GHz frequency range. A four-stage, common-source, unconditionally stable monolithic microwave integrated circuit (MMIC) design is presented using the state-of-the-art 35 nm indium phosphide HEMT process from Northrop Grumman Corporation. The simulated MMIC achieves noise temperature (T_e) lower than 58 K across the operational bandwidth, with average T_e of 38.8 K (corresponding to less than 5 times the quantum limit (hf/k) at 170 GHz) and forward transmission of 20.5 ± 0.85 dB. Input and output reflection coefficients are better than -6 and -12 dB, respectively, across the desired bandwidth. To the authors knowledge, no LNA currently operates across the entirety of this frequency range. Successful fabrication and implementation of this LNA would challenge the dominance SIS mixers have on sub-THz receivers
SiGe HBT X-Band LNAs for Ultra-Low-Noise Cryogenic Receivers
We report results on the cryogenic operation of two
different monolithic X-band silicon-germanium (SiGe) heterojunction bipolar transistor low noise amplifiers (LNAs) implemented in a commercially-available 130 nm SiGe BiCMOS platform. These SiGe LNAs exhibit a dramatic reduction in noise temperature with cooling, yielding Teff of less than 21 K (0.3 dB noise figure) across X-band at a 15 K operating temperature. To the authors’ knowledge, these SiGe LNAs exhibit the lowest broadband noise of any
Si-based LNA reported to date
Design of Active Waweguide OMT for Radio Astronomy Receiver Array in the 3 MM Band
We describe the design of an integrated cryogenic receiver module based on an “active” waveguide Orthomode Transducer (OMT) for dual-polarization radio astronomy observations across 75-116 GHz (3-mm band). The receiver module consists of passive and active sections that can be incorporated in a very compact mechanical assembly suitable for integration in a focal plane array.
The passive section of the receiver module employs a broadband backward-coupler waveguide OMT while the active section consists of ultra-low noise MMIC (Monolithic Microwave Integrated Circuit) amplifiers
Ultra-low-noise microwave amplifiers
The highlights of 20 years of maser use and development are presented. Masers discussed include cavity, traveling wave, K band, and S band. Noise temperatures measured since 1960 are summarized. Use of masers in the Deep Space Network is presented. Costs associated with the construction of masers systems are given
An Experiment and Detection Scheme for Cavity-based Cold Dark Matter Searches
A resonance detection scheme and some useful ideas for cavity-based searches
of light cold dark matter particles (such as axions) are presented, as an
effort to aid in the on-going endeavors in this direction as well as for future
experiments, especially in possibly developing a table-top experiment. The
scheme is based on our idea of a resonant detector, incorporating an integrated
Tunnel Diode (TD) and a GaAs HEMT/HFET (High Electron Mobility
Transistor/Heterogenous FET) transistor amplifier, weakly coupled to a cavity
in a strong transverse magnetic field. The TD-amplifier combination is
suggested as a sensitive and simple technique to facilitate resonance detection
within the cavity while maintaining excellent noise performance, whereas our
proposed Halbach magnet array could serve as a low-noise and permanent solution
replacing the conventional electromagnets scheme. We present some preliminary
test results which demonstrate resonance detection from simulated test signals
in a small optimal axion mass range with superior Signal-to-Noise Ratios (SNR).
Our suggested design also contains an overview of a simpler on-resonance dc
signal read-out scheme replacing the complicated heterodyne readout. We believe
that all these factors and our propositions could possibly improve or at least
simplify the resonance detection and read-out in cavity-based DM particle
detection searches (and other spectroscopy applications) and reduce the
complications (and associated costs), in addition to reducing the
electromagnetic interference and background.Comment: 22 pages, 7 figure
The Expanded Very Large Array
In almost 30 years of operation, the Very Large Array (VLA) has proved to be
a remarkably flexible and productive radio telescope. However, the basic
capabilities of the VLA have changed little since it was designed. A major
expansion utilizing modern technology is currently underway to improve the
capabilities of the VLA by at least an order of magnitude in both sensitivity
and in frequency coverage. The primary elements of the Expanded Very Large
Array (EVLA) project include new or upgraded receivers for continuous frequency
coverage from 1 to 50 GHz, new local oscillator, intermediate frequency, and
wide bandwidth data transmission systems to carry signals with 16 GHz total
bandwidth from each antenna, and a new digital correlator with the capability
to process this bandwidth with an unprecedented number of frequency channels
for an imaging array. Also included are a new monitor and control system and
new software that will provide telescope ease of use. Scheduled for completion
in 2012, the EVLA will provide the world research community with a flexible,
powerful, general-purpose telescope to address current and future astronomical
issues.Comment: Added journal reference: published in Proceedings of the IEEE,
Special Issue on Advances in Radio Astronomy, August 2009, vol. 97, No. 8,
1448-1462 Six figures, one tabl
Design and performance of the ADMX SQUID-based microwave receiver
The Axion Dark Matter eXperiment (ADMX) was designed to detect ultra-weakly
interacting relic axion particles by searching for their conversion to
microwave photons in a resonant cavity positioned in a strong magnetic field.
Given the extremely low expected axion-photon conversion power we have
designed, built and operated a microwave receiver based on a Superconducting
QUantum Interference Device (SQUID). We describe the ADMX receiver in detail as
well as the analysis of narrow band microwave signals. We demonstrate the
sustained use of a SQUID amplifier operating between 812 and 860 MHz with a
noise temperature of 1 K. The receiver has a noise equivalent power of
1.1x10^-24 W/sqrt(Hz) in the band of operation for an integration time of
1.8x10^3 s.Comment: 8 pages, 12 figures, Submitted to Nuclear Inst. and Methods in
Physics Research,
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