Temperature range, SQUIDs

Magnetic measurements were carried out on a SQUID magnetometer. Zero field cooled (ZFC) and field cooled (FC) magnetization data were collected in the temperature range of 2-350 K with an applied field of 100 Oe. 

An aspect of importance to some laboratory applications of dc SQUIDs that were developed and are used at IBM is that the SQUIDs operate over a broad temperature range. For instance, small particle susceptometers must have samples in intimate contact with them such that the entire SQUID has to be warmed and cooled with the experiment (47). High Tc material could potentially extend the temperature range approximately 10 fold. 

Simple SQUID devices in a few forms have already been demonstrated to operate in the liquid nitrogen temperature range. Koch et al. (48) successfully operated at 68 K a one-layer thin film dc SQUID with long, granular, weak-link bridges, while Iguchi et al. (49) and Zimmerman et al.(50) successfully operated rf- and dc-SQUIDs, respectively, based on bulk ceramic loops... 

Our commercially available polyaniline powder, ORMECON powder, was used for preparing the PAni-PMMA blends. The magnetic susceptibility of unblended PAni and PAni-PMMA blends was measured using a commercial SQUID magnetometer in the temperature range of 2.0-300 K in an applied magnetic field of 100 mT. 

Fig. 1 Image of a Superconducting Quantum Interference Device SQUID) MPMS XL 7, Quantum Design. Magnetic field range 7 T, temperature range 1.7-400 K (Institute of Physics, Karl-Franzens-University Graz)...

Figure 10.3a shows the temperature dependence of the effective magnetic moments determined by SQUID for the microcrystalline sample of Fe(OETPP) [34]. The jtiefr values are 3.8-3.9jtiB in a wide temperature range, which are quite close to the spin-only value, 3.87/tiB. expected for the S = 3/2 state. Figure 10.3b shows the Mossbauer spectrum of the same complex taken at 77 K for the microcrystalline sample. The IS and QS values are 0.42 and 3.02 mms , respectively. The large QS value supports that the complex adopts the intermediate-spin state [38-40]. 

Solid State Magnetic Susceptibility Measurements were conducted with a MPMS-XL 5T superconducting quantum interference device (SQUID) from Quantum Design at the University of Heidelberg in collaboration with Professor Peter Comba and recorded as a function of the apphed field (0-5 T), and at temperatures ranging from 2 to 300 K (zero field cooled method). The powdered samples were pressed into a PTEE band to avoid field-induced orientation of the... 

The crystals of SnNbsSe were obtained by dissolution of the A15 Nb3Sn superconductor in the dichalcogenide 2H-NbSe2 according to the method described in [1], The crystal sizes ranged from lxlx0.5 to 3x3x1 mm3. Preliminary susceptibility study of the compound by SQUID technique demonstrated temperature superconductivity transition at T 17.5 K [ 1 -3]. 

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