Applications SQUIDs

Superconductor Applications SQUIDs and Machines, ed. B. n Schwartz and S. Foner (Plenum Press, New York 1976). 

Electrophysiological protocols utilizing crayfish and squid giant axons revealed that external application of brevetoxin caused a concentration-dependent... 

Magnetocrystalline anisotropy constant, of M-type ferrites, 11 67, 68 Magnetohydrodynamic (MHD) convection, in microfluidic mixers, 26 967 Magnetohydrodynamic power generation, cesium application, 5 704 Magnetometers, SQUID, 23 871... 

The SQUID obviously has several potential advantages for on-line applications. It can operate at very low inhomogeneous magnetic fields, avoiding the need for large expensive shimmed magnets. It also does not require tuning and has very low power requirements. However there are also severe technical limitations to be overcome before it can be used in on-line commercial operations. The whole SQUID needs to be immersed in liquid helium and a conventional RF coil is still needed to excite the NMR resonance. It remains to be seen whether such devices will find future on-line application in horticulture. 

Octopuses, squid, cuttlefish, and nautiloids are also other common food source for many of the Asians because of their importance of potentiality in medical applications. More specifically, octopus and squids are well explored in Asian countries due to their traditional medical values. 

SQUID sensors as high-sensitivity devices for a variety of applications were presented in a talk by S. Bondarenko (SQUID-based magnetic microscope). 

C. Hilbert and J. Clarke, SQUID 85, Proceedings of the International Conference on SQUID Devices and Their Applications, H. D. Hahlbohm and H. Lubbit, eds., Walter de Gruyter, Berlin 1985. 

An application of Josephson junctions is in superconducting quantum interference devices (SQUIDS). Figure 4.61 shows two Josephson junctions passing a current with a magnetic induction B, through the ring of area A. 

Saffman, P.G. (1977), Results of a two-equation model for turbulent flows and development of relaxation stress model for application to staining and rotating flows. Proceedings of Project SQUID Workshop on Turbulence in Internal Flows, Hemisphere, New York, p. 191. 

Konrad, J. H. (1977) An Experimental Investigation of Mixing in Two-Dimensional Turbulent Shear Flows with Applications to Diffusion-Li mi ted Chemical Reaftions, SQUID Technical Report, C1T-8-PU. 

Enpuku K, Minotani T, Gima T et al (1999) Detection of magnetic nanoparticles with superconducting quantum interference device (SQUID) magnetometer and application to immunoassays. Jpn J Appl Phys 38 L1102-L1105... 

Enpuku K, Minotani T, Hotta M, Nakahodo A (2001) Application of High Tc SQUID magnetometer to biological immunoassays. IEEE Trans on Appl Supercond 11 661-664... 

Figure 3. Sodium currents recorded from the squid giant axons before (A) and after (B) internal application of 10 pM deltamethrin. External and internal sodium concentrations were 111 mM and 50 mM, respectively. A, a depolarizing pulse from the holding potential (V ) of -80 mV to -20 mV elicited the normal transient inward sodium current which decayed within 10 msec. Depolarization to a second depolarizing pulse (500 msec) to the sodium reversal potential (E a - +20 mV) yielded a negligible current. Repolarization to the holding potential (-80 mV) produced a very small inward sodium tail current. B, the same pulse protocol as that for A but in the presence of deltamethrin in another axon Note a large and prolonged tail current upon repolarization from +20 mV to -80 mV.

It was aheady mentioned that one of the major advantages for the application of organic semiconductors in spintronics applications is the large spin diffusion length even at room temperature. While most of the spintronics experiments published up to now are performed at very low temperature, it is assumed that applying organics makes this effort non-essential. For this reason SQUID measurements were also carried out at room temperature in order to check if the magnetic behaviour of the contacts still allows spinFET operation. 

Figure 28.7 compares two SQUID measmements on one sample, taken at 4 K and room temperature. The results show that at room temperatmes the absolute values of the switching fields are significantly reduced, whereas the remnant magnetisation is hardly affected. The average width of the plateaus at room temperature is determined as 73 Oe. This is still considered sufficient for spinQFET application. 

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