Noise Properties of High Temperature Superconducting Bolometers

Abstract

The review describes the noise properties of the high temperature superconducting (HTS) bolometers developed for the applications in the optical electronic devices of infrared and submillimeter wave-lengths. The principle of high-Tc transition edge bolometer operation and bolometer noise theory are considered, taking into account the peculiarities of constant bias current and constant bias voltage modes. The published results of bolometer noise modeling are discussed. Various sources of the excess 1/f-noise in HTS films as temperature sensitive element for bolometer are reviewed, including the experimental data and modern noise models. Comparative analysis of noise characteristics of the most developed HTS bolometers for application (antenna-coupled microbolometers and bolometers based on silicon micromachining technology) is reported.

Noise Modelling of Absolute High-Tc Superconducting Measuring Instrument for X-ray Synchrotron Radiation

“…The phonon noise contribution does not depend on frequency and ETF does not influence NEP ph . The depression of the 1/f-contribution is due to larger value of coefficient E in CVM (see Table), the depression of the Johnson noise contribution is due to larger Joule power P b in CVM [8]. The increase of NEP 1/f and NEP R begins at range of f>f cut where responsivity decreases.…”

“…The theoretical estimation of the influence of the different noise components on the noise equivalent power (NEP) and the detectivity (D*) of bolometers, operating in constant current mode (CCM) with positive ETF and CVM with negative passive ETF and active ETF at various G b , T b , R b , noise Hooge parameters D H of YBaCuO films, substrate materials, area size was carried out. The results of estimation, using the theory developed in [4][5][6]8,9], are shown in Table 1 and on Figures 1,2.…”

“…At calculations for CVM the value of the sink temperature is equal 80 K, the operation point is selected at temperature with maximum of E, the values of D H at normal state: 0.09 -for film on Al 2 O 3 and 10 -3 -on SrTiO 3 [8]. Table and Figures show that the use of the passive CVM permits to decrease time constant W e , for example, bolometer on SrTiO 3 substrate in ~ 37 times and operate with modulation frequency up to 28 Hz, reaching NEP limited by only phonon noise.…”

“…The negative FTF decreases the time constant as W e =W 0 /(1+L 0 ), where W 0 and W e is intrinsic and effective thermal time constants. Note, the noise properties of HTS bolometer depends on the ETF as well [5,8]. In contrast to passive CVM operation, the improvement in the bolometer time response can be obtained using analogue electronic feedback control as well [7].…”

Noise Limitations of Miniature Thermistors and Bolometers

“…The 1/f noise is significant in the high-Tc superconductors. The H values range from 5*10 -4 to 1.4*10 3 for different material compositions (Khrebtov, 2002). The epitaxial growth of the sensitive layer decrease the 1/f noise (de Nivelle et al 1997), however, the H values show rather large scatter between the samples prepared in the same run, further H depends also on the value in the same sample, i.e.…”