A thermal memory cell

Journal of Applied Physics (Impact Factor: 2.19). 09/2009; DOI: 10.1063/1.3207791
Source: IEEE Xplore

ABSTRACT We present a concept of a new kind of memory element, a thermal memory cell, where a byte of digital information can be stored into the storage medium by pure thermal manipulation. Thermal inscription of information employs a specific temperature-time profile that involves continuous cooling and isothermal waiting time periods in the absence of any external magnetic or electric field. Our storage media are magnetically frustrated solids. We succeeded to thermally write arbitrary American Standard Code for Information Interchange characters into the Taylor-phase T -Al 3( Mn , Fe ) complex intermetallic compound and the Cu–Mn canonical spin glass. Besides for data storage, the concept may be employed for secure data transfer and for retrieving cosmological information from extraterrestrial dust particles.

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