Spin Glass Superconductors for Programmable Read-Only Memory
Original Publication Date: 1983-Jul-01
Included in the Prior Art Database: 2005-Feb-07
Recently spin glass superconductors have been discovered 1, 2 which have interesting properties discussed below. Consider the case of GdxLa1-xOs2 as an example. The phase diagram is shown in Fig. 1. The second property (not discussed in the publications) is that when a composition, such as x = 15% in Fig. 1, is cooled in a magnetic field of, for example, about 100 Oe or so, through the spin glass transition temperature (Tsg), a magnetization is frozen in. Then, even if the external field is turned off, superconductivity is destroyed, i.e., Tsupercond drops to zero. Already several degrees below Tsg, the decay of remanent M is so slow as to be negligible for storage times of interest; so this effect forms a novel kind of memory.