Handbook of High Temperature Superconductor Electronics Part 12 docx

... (12) Dividing Eq. (12) by the square of the magnitude of ℜ K/W from Eq. (8) (and as- suming unity ␩), temperature fluctuations of the detector thereby correspond to an apparent fluctuation of ... are a couple of reasons why dR/dT may depend on the magnitude of the bias current. The first is thermal. R versus T is logically interpreted in terms of T film , the temperature o...

Ngày tải lên: 10/08/2014, 19:20

... formation of Tl-Ba-Ca-Cu-O(TBCCO) compounds proceeds by the fol- lowing sequences: Tl(2201)–Tl(2 212) –Tl(2223)–Tl (122 3)–Tl (123 4)–Tl (124 5) or Tl(2201)–Tl(2 212) –Tl(2223)–Tl (121 2). The toxicity of Tl ... pre- carious balance between the high temperatures required to form the superconduct- ing phases and the high volatility of Tl at these temperatures. The partial pressures...

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... reports of imaging of the distribution of eddy current at a frequency below about 1 MHz (162), a microwave source of frequency up to 12. 5 GHz at 77 K (178), and a microwave source at room temperature ... due to the complexity of the system and the requirement of liq- uid helium. With the development of a high- T c SQUID with sufficiently high sen- sitivity, the interest...

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... 10 High- Temperature Superconductor Microwave Devices Neeraj Khare 11 High- Temperature Superconducting IR Detectors John C. Brasunas 12 Cryocoolers and High- T c Devices Ray Radebaugh 13 High- Temperature ... Conductance Noise in High- Temperature Superconductors László Béla Kish 6 Noise in High- Temperature Superconductor Josephson Junctions J.C. Macfarlane, L. Hao, an...

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... structure of HgBa 2 CuO 4 (Hg -120 1), HgBa 2 CaCu 2 O 6 (Hg- 121 2), and HgBa 2 Ca 2 Cu 3 O 8 (Hg -122 3) is similar to that of Tl -120 1, Tl -121 2, and Tl -122 3 (Fig. 1.4) with Hg in place of Tl (21). ... increases. For Hg -120 1, Hg -121 2, and Hg -122 3, the values of T c are 94, 128 , and 134 K respectively, as shown in Table 1.1. The observation that the T c of Hg -122 3 i...

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... anisotropic nature of high- temperature superconductor materials, mismatch in the lattice and thermal expansion coefficient between the superconductor and N-layer, chemical incompatibility between the superconductor ... the fabrica- tion of high- temperature superconducting ramp-edge SNS junctions and SQUIDs. 86 Jia F IGURE 3.1 Cross-sectional diagram of a ramp-edge superco...

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... 10 3 –10 4 A/cm 2 . The value of ␳ N is of the order of 10 -7 –10 -9 ⍀ и cm 2 and is almost independent of the temperature. Step-Edge Josephson Junctions 119 FIGURE 4 .12 Schematic representation of the procedure ... Junctions 115 FIGURE 4.10 High- temperature TEM image of the GB formed at the bottom edge of a high- angle LaAlO 3 step. (From Ref. 22.) F IGURE 4.11 (a) Ske...

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... 5.3.1.1 “Bulk” Temperature Regime At the high- temperature part of the conductorn superconductor transition region, when the resistance has significantly decreased (the onset of superconductivity has ... independent of the temperature. Note: Although a significant part of HTS samples show this behavior especially materials of lower quality, the bulk regime is often missin...

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... significant parts of these devices are generally noisier. The reason of the higher noise level of the all types (dc and RF) of high- T c SQUIDs may be discrete or a large ensemble of Josephson ... predictions of the theory of the model of an ensemble of independent fluctuators. Far from T c (see the curve for T ϭ 8 K), the values of S ⌽ (␻) at frequency of 1 Hz are only...

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... I c R n product of HTS junctions can also be expected to be larger than that of LTS junctions because it intrinsically depends on the gap voltage of the superconductor. A number of tests of the RSFQ ... Pd, and Pd/Au (30). Among of them, Pd/Au had a much smaller temperature coefficient and higher resistance, espe- cially at low -temperature, than Pd. The sheet resistance of 4...

Ngày tải lên: 10/08/2014, 19:20