Recent progress in HTSC bolometric and nonbolometric detectors

Abstract

The main phenomena that may be responsible of radiation detecting mechanisms in superconductors are described in a first part of this paper. Several examples are given, ranging from broadband and sensitive bolometric devices to ultrafast nonbolometric infrared detectors. The second part is devoted to the study of various transition edge bolometers designed to be built at low cost. Polycrystalline zirconia substrates have been used, to grow YBaCuO films by both in situ and ex situ oxygenation after radiofrequency sputtering. The voltage responsivity at 10.6 im wavelength has been studied with respect to the modulation frequency of the incident radiation, both experimentally and theoretically. A 2D thermal model has been developped, allowing to interpret the complex (amplitude and phase) experimental frequency responses of various devices. In particular, the amplitude response can be described as a succession off andf112 segments. Noise measurements show NEP and detectivity values reaching a very satisfactory level for granular films.

Recent progress in high-temperature superconductor bolometric detectors: from the mid-infrared to the far-infrared (THz) range

“…Hz) and τ = 9 ms. Our application for this device was the prediction of the responsivity with the help of a theoretical model, including both film and substrate thermal data plus film-substrate interface conductance [23]. An eight-pixel matrix was realized by Mai et al [24] who ion milled a 300 nm thick YBaCuO film deposited onto 200 µm thick YSZ.…”

“…The reported performance (obtained at λ = 7.5 µm) are more modest: R v = 1.4 V W −1 and NEP = 2 × 10 −10 W Hz −1/2 (f m = 10 Hz), with τ = 200 ms. An original feature of the device was the integration of a submillimetre antenna microbolometer as the second channel. [23] developed economical YBaCuO 'minibolometers' elaborated on polycrystalline YSZ slabs thinned down to 80 µm. These 10 × 0.5 mm 2 suspended substrates were thermally isolated from the cold thermostat by two zirconia legs.…”

“…The D * ∝ τ 1/2 trend is discussed in the text. Label references: HgCdTe [57]; Be1 [22], Br1 [17], Dwi [19], Eid [26], For [16], Leu [15], LiK [25], Rob [28], Ton [21]; Bal [37], Be2 [22,23], Ber [34], Bot [36], Br2 [31], Epi [38], Khr [33], Lak [32], LiH [35], Ver [29]; Bar [51], Foo [50], Joh [49], LiQ [41], Méc [52], Nef [43], Ni1 [46] and Ni2 [48].…”