# Direct current superconducting quantum interferometers with asymmetric shunt resistors

@article{Rudolph2012DirectCS, title={Direct current superconducting quantum interferometers with asymmetric shunt resistors}, author={Matthias Rudolph and Joachim Nagel and Johannes Maximilian Meckbach and Matthias Kemmler and M. Siegel and Konstantin Ilin and Dieter Koelle and Reinhold Kleiner}, journal={Applied Physics Letters}, year={2012}, volume={101}, pages={052602} }

We have investigated asymmetrically shunted Nb/Al-AlOx/Nb direct current (dc) superconducting quantum interference devices (SQUIDs). While keeping the total resistance R identical to a comparable symmetric SQUID with R−1=R1−1+R2−1, we shunted only one of the two Josephson junctions with R=R1,2/2. Simulations predict that the optimum energy resolution ϵ and thus also the noise performance of such an asymmetric SQUID can be 3–4 times better than that of its symmetric counterpart. Experiments at a…

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## References

SHOWING 1-10 OF 24 REFERENCES

Improved superconducting quantum interference devices by resistance asymmetry

- Physics
- 2001

Direct current superconducting quantum interference devices made by Josephson junctions with asymmetric shunt resistances have been numerically investigated in the low temperature regime. When…

Characteristics of asymmetric superconducting quantum interference devices

- Physics
- 2001

Direct current-superconducting quantum interference devices (SQUIDs) characterized by asymmetric Josephson junctions have never been used for applications. In order to demonstrate their potential…

Low-noise magnetometers with asymmetric superconducting quantum interference devices

- Physics
- 2001

Fully integrated low-critical-temperature magnetometers based on asymmetric superconducting quantum interference devices have been designed, fabricated, and characterized. The large value of the flux…

Current amplification with asymmetric direct current superconducting quantum interference devices at 77 K

- Physics
- 1996

One can use a direct current (dc) superconducting quantum interference device (SQUID) as a current amplifier by injecting a signal current Is into part of the superconducting loop and detecting the…

dc SQUID: Noise and optimization

- Physics
- 1977

A computer model is described for the dc SQUID in which the two Josephson junctions are nonhysteretic, resistively shunted tunnel junctions. In the absence of noise, current-voltage(I–V)…

Noise characteristics of a dc SQUID with a resistively shunted inductance

- Physics
- 1985

Noise characteristics of a dc SQUID with an inductance shunted by a damping resistance are studied numerically. It is shown that the damping resistance improves considerably the resolution of the…

Superconducting quantum interference device with very low magnetic flux noise energy

- Physics
- 1982

We have fabricated dc superconducting quantum interference devices incorporating Josephson tunnel junctions with an inductance of about 2 pH and a capacitance per junction of about 0.3 pF. The lowest…

A Numerical Treatment of the rf SQUID: II. Noise Temperature

- Physics
- 2007

Abstract
We investigate rf SQUIDs (Superconducting QUantum Interference Devices), coupled to a resonant input circuit, a readout tank circuit and a preamplifier, by numerically solving the…

Performance of high-T/sub c/ dc SQUID magnetometers with resistively shunted inductances compared to "unshunted" devices

- Physics
- 2001

We have investigated resistively shunted direct-coupled high-T/sub c/ dc SQUID magnetometers with different inductances. At T=77 K, good quantitative agreement was observed between the measured…

A Numerical Treatment of the rf SQUID: I. General Properties and Noise Energy

- Physics
- 2007

Abstract
We investigate the characteristics and noise performance of rf Superconducting Quantum Interference Devices (SQUIDs) by solving the corresponding Langevin equations numerically and…