Tg. Henrici et al., NOISE CHARACTERISTICS OF YBCO C-AXIS MICROBRIDGE JUNCTIONS, IEEE transactions on applied superconductivity, 7(2), 1997, pp. 3335-3338
We present measurements of the noise properties of YBCO c-axis Microbr
idge (CAM) Junctions. The junctions have been characterised in terms o
f their electrical and noise properties over range of temperature and
frequency. The methods used provide both very high sensitivity measure
ments in a narrow frequency band (60 kHz), and moderate sensitivity me
asurements in a broad band (0.01 - 10 kHz). The normalised levels of c
ritical current fluctuations and normal resistance fluctuations are fo
und to be comparable to earlier measurements carried out on grain boun
dary junctions at both 100 Hz and 60 kHz. The 60 kHz results can be mo
delled reasonably successfully with the same model developed to descri
be grain boundary junctions. The frequency dependence is close to 1/f,
but has some Lorentzian shaped deviations appearing for many of the j
unctions examined. These structures are both temperature and bias curr
ent dependent.