Control of the responsivity and the detectivity of superconductive edge-transition YBa2Cu3O7-x bolometers through substrate properties

Citation
M. Fardmanesh et al., Control of the responsivity and the detectivity of superconductive edge-transition YBa2Cu3O7-x bolometers through substrate properties, APPL OPTICS, 38(22), 1999, pp. 4735-4742
Citations number
24
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
APPLIED OPTICS
ISSN journal
00036935 → ACNP
Volume
38
Issue
22
Year of publication
1999
Pages
4735 - 4742
Database
ISI
SICI code
0003-6935(19990801)38:22<4735:COTRAT>2.0.ZU;2-H
Abstract
The detectivity D* limits of YBa2Cu3O7-x bolometer on 0.05-cm-thick crystal line substrates are investigated, and a method to increase D* to greater th an 10(9) (cm Hz(1/2))/W at a 20-mu m wavelength is proposed. Because the re sponse increases proportionally with the bias current I-b, whereas the nois e near T-c (the transition or critical temperature) of our MgO and SrTiO3 s ubstrate samples does not, an increase in D* of these samples is obtained b y an increase in I-b. Another limiting factor is the de thermal conductance G(0) of the device, which, although controlled by the substrate-holder the rmal boundary resistance for our samples, can be changed by means of thinni ng the substrate to increase D*. The optimal amount of thinning depends on the substrate's thermal parameters and the radiation modulation frequency. D* in our samples is also found to follow the spectral-radiation absorption of the substrate material. (C) 1999 Optical Society of America.