Magnetic tunnel effect
In 1975 Julliere [1] discovered the effect of tunnel magnetoresistance (TMR). If two ferromagnets (Fe in his case) are separated by a thin (about 1 nm) insulator (Ge in his case) the resistance of the tunneling current changes with the relative orientation of the two magnetic layers. The resistance is normally higher in the anti-parallel case.
Room temperature TMR was discovered 1995 by Moodera et. al. after the interest has been renewed in this field by the discovery of giant magnetoresistance [3,4]. It is now the base for the magnetic random access memory (MRAM). For more scientific information see [5].
References:
[1] Julliere et. al., Phys. Lett. 54A, 225 (1975)
[2] J. S. Moodera et. al., Phys. Rev. Lett. 25, 1270 (1995)
[3] G. Binasch et. al., Phys. Rev. B 39, 4828 (1989)
[4] M. N. Baibich et. al., Phys. Rev. Lett. 61, 2472 (1988)
[5] Moodera and Mathon, Magn. Magn. Mater. 200, 248 (1999)
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