Title :
Modeling frequency fluctuations and noise thermometry using an R-SQUID noise thermometer
Author :
Soulen, R.J. ; Fogle, W.E. ; Colwell, J.H.
Author_Institution :
US Naval Res. Lab., Washington, DC, USA
fDate :
4/1/1993 12:00:00 AM
Abstract :
The white and additive noise generated by an R-SQUID noise thermometer whose temperature was varied from 6.3 mK to 0.738 K is measured. Room temperature simulations of the effect of white and additive noise on the circuit used to measure the noise for the R-SQUID are conducted. It is shown that the measured noise in all cases was fit to within the 0.1% statistical measurement imprecision by a model for the R-SQUID based on frequency modulation. This conformity is sufficiently good that any deficiencies in either do not lead to systematic inaccuracies in the noise temperature scale which exceed 0.1%. Comparisons of the R-SQUID with several other thermometers indicate that the overall agreement is at worst 0.2%
Keywords :
SQUIDs; electric noise measurement; electron device noise; fluctuations; frequency modulation; frequency stability; low-temperature techniques; oscillators; thermometers; white noise; 6.3 mK to 0.738 K; R-SQUID noise thermometer; additive noise; frequency fluctuations; frequency modulation; frequency standard; model; noise thermometry; oscillator noise; resistor; simulations; white noise; Additive noise; Circuit noise; Counting circuits; Fluctuations; Frequency measurement; Noise generators; Noise measurement; Oscillators; Temperature; Time measurement;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
