Microstrip superconducting quantum interference device amplifiers with submicron Josephson junctions: Enhanced gain at gigahertz frequencies

DeFeo, M. P.; Bhupathi, P.; Yu, K.; Heitmann, T. W.; Song, C.; McDermott, R.; Plourde, B. L. T.
August 2010
Applied Physics Letters;8/30/2010, Vol. 97 Issue 9, p092507
Academic Journal
We present measurements of an amplifier based on a dc superconducting quantum interference device (SQUID) with submicron Al–AlOx–Al Josephson junctions. The small junction size reduces their self-capacitance and allows for the use of relatively large resistive shunts while maintaining nonhysteretic operation. This leads to an enhancement of the SQUID transfer function compared to SQUIDs with micron-scale junctions. The device layout is modified from that of a conventional SQUID to allow for coupling signals into the amplifier with a substantial mutual inductance for a relatively short microstrip coil. Measurements at 310 mK exhibit gain of 32 dB at 1.55 GHz.


Related Articles

  • Microstrip direct current superconducting quantum interference device radio frequency amplifier: Noise data. Schmidt, Bernd; Mück, Michael // Applied Physics Letters;4/9/2012, Vol. 100 Issue 15, p152601 

    A series of about twenty superconducting quantum interference devices (SQUIDs) has been operated as microstrip-SQUID amplifiers (MSAs) at frequencies ranging from 100 MHz to 2 GHz to study the dependence of their gain and noise temperature on bias current and flux. The measured values were in...

  • Planar-type MgB2 SQUIDs utilizing a multilayer process. Cunnane, Daniel; Galan, Elias; Chen, Ke; Xi, X. X. // Applied Physics Letters;11/18/2013, Vol. 103 Issue 21, p212603 

    We report planar-type MgB2 DC SQUIDs fabricated using a multilayer process. The SQUIDs employed sandwich-type MgB2/MgO/MgB2 Josephson junctions and a MgB2 wiring layer. The SQUIDs showed large voltage modulation above 500 μV at 15 K and operated in a broad temperature range from 15 to 37 K...

  • Very low noise, tightly coupled, dc SQUID amplifiers. Muhlfelder, B.; Beall, J. A.; Cromar, M. W.; Ono, R. H. // Applied Physics Letters;10/27/1986, Vol. 49 Issue 17, p1118 

    We have fabricated and tested thin film, niobium edge junction, double transformer, dc superconducting quantum interference devices (SQUID’s) that were stable under room-temperature storage and thermal cycling and that had very good noise performance. The input inductance, approximately...

  • Effect of an input coil microwave resonance on dynamics and noise properties of a dc... Polushkin, V.; Glowacka, D.; Hart, R.; Lumley, John // Review of Scientific Instruments;Mar99, Vol. 70 Issue 3, p1713 

    Explores the capabilities of superconducting quantum interference device (SQUID) as a fast current amplifier. Requirement of the integration of a spiral input coil on top of the SQUID washer; Spectral density of the intrinsic magnetic flux noise; Intrinsic energy resolution; Coupled energy...

  • Improved dc SQUID read-out electronics with low 1/f noise preamplifier. Drung, Dietmar // Review of Scientific Instruments;Nov97, Vol. 68 Issue 11, p4066 

    Presents an improved read-out electronics without flux modulation for direct current (dc) superconducting quantum interferences devices (dc SQUID); Preamplifier's direct coupling to the SQUID; Essential specifications of practical SQUID systems determined by using liquid-helium and...

  • Nonperiodic flux to voltage conversion of series arrays of dc superconducting quantum interference devices. Ha¨ussler, Ch.; Oppenla¨nder, J.; Schopohl, N. // Journal of Applied Physics;2/1/2001, Vol. 89 Issue 3, p1875 

    We present a theoretical study on the voltage response function of series arrays of dc superconducting quantum interference devices (SQUIDs) for which the elementary dc SQUID loops vary in size and, possibly, in orientation. If the distribution of the array loop sizes is chosen according to...

  • Superconducting quantum interference device amplifiers at gigahertz frequencies. Mück, Michael; Welzel, Christian; Clarke, John // Applied Physics Letters;5/12/2003, Vol. 82 Issue 19, p3266 

    A series of five dc superconducting quantum interference devices (SQUIDs) have been operated as microstrip amplifiers at frequencies ranging from 2.2 to 7.4 GHz. In these devices, the signal is connected between the SQUID washer and coil, which acts as a microstrip resonator. The gain measured...

  • Stroboscopic single-shot detection of the flux state in a radio frequency superconducting quantum interference device. Cosmelli, C.; Sciamanna, F.; Castellano, M. G.; Leoni, R.; Torrioli, G.; Carelli, P.; Chiarello, F. // Applied Physics Letters;4/29/2002, Vol. 80 Issue 17, p3150 

    The flux states of a rf superconducting quantum interference device (SQUID) can be used to investigate macroscopic quantum effects, the most challenging of which is the detection of quantum coherent oscillations, and are promising candidates for the implementation of quantum computing. The use...

  • Equivalent parameters of a Josephson junction in a microwave SQUID structure. Vendik, O. G.; Danilov, I. S. // Technical Physics;Nov99, Vol. 44 Issue 11, p1360 

    The equivalent parameters of a Josephson junction in a microwave SQUID structure are calculated on the basis of relations obtained as a result of an analysis of the operation of an rf SQUID. This analysis is based on the sawtooth variation of the voltage on the resonator as a function of the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics