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We have analyzed a radio-frequency single-electron-transistor (RF-SET) circuit that includes a high-electron-mobility-transistor (HEMT) amplifier, coupled to the single-electron-transistor (SET) via an impedance transformer. We consider how power is transferred between different components of the circuit, model noise components, and analyze the operating conditions of practical importance. The results are compared with experimental data on SETs. Good agreement is obtained between our noise model and the experimental results. Our analysis shows, also, that the biggest improvement to the present RF-SETs will be achieved by increasing the charging energy and by lowering the HEMT amplifier noise contribution. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have fabricated and characterized an electrometer that couples two parallel single-electron transistors (SETs) to a single radio-frequency (RF) tank circuit for use as a differential RF-SET. We demonstrate operation of this device in summing, differential, and single-SET operation modes, and use it to measure a Coulomb staircase from a differential single Cooper-pair box. In differential mode, the device acts to screen out correlated input signals while being sensitive to anticorrelated signals. [ABSTRACT FROM AUTHOR]

We demonstrate a high-performance cryogenic amplifier based on a radio-frequency single-electrontransistor (rf-SET). The high charge sensitivity and large bandwidth of the rf-SET, along with low power dissipation, low capacitance and on-chip integrability, make it a good candidate for a general-purpose cryogenic amplifier for high impedance sources. We measure a large-gate rf-SET with an open-loop voltage noise of 30 nV/√(Hz), among the lowest reported voltage noise figures for a SET. Using a closed-loop transimpedance configuration, the amplifier shows almost 2 orders of magnitude increase in dynamic range, a 3 dB bandwidth of 30 kHz, and a transimpedance gain of 50 V/µA for a cryogenic 1 MΩ load resistor. The performance of this amplifier is already sufficient for use as an integrated readout with some types of high-performance cryogenic detectors for astrophysics. [ABSTRACT FROM AUTHOR]

We have fabricated an aluminum single-electron transistor and characterized it at frequencies up to 10 MHz by measuring the reflected signal from a resonant tank in which the transistor is embedded. We measured the charge sensitivity of this radio-frequency single-electron transistor to be 3.2 x 10[sup -6] e/√Hz, which corresponds to the uncoupled energy sensitivity of 4.8 ... Our measurements indicate that with further improvements, the radio-frequency single-electron transistor could reach the shot-noise limit estimated to be about 1 ... [ABSTRACT FROM AUTHOR]

We have studied possible implementations of high-resistance tunnel barriers for an all-YBa2Cu3O7−δ superconducting single-electron transistor (SSET). The step-edge and biepitaxial techniques have been employed to fabricate the junctions. Both technologies appear very promising for the implementation of all-high-Tc SSET. [Copyright &y& Elsevier]