Dynamic Thermomagnetic Writing in Tunnel Junction Cells Incorporating Two GeSbTe Thermal Barriers

Magnetic tunnel junctions (MTJs) incorporating GeSbTe thermal barriers and weakly pinned free layers (H
_ex
~60Oe) have been produced with areas between 1times1 mum
²
and 3times8 mum
²
. Current pulses lasting from 100 mus down to 20 ns were used to heat the MTJs and reverse the free layer pinning field. It is demonstrated that pulses with 7 mW/mum
²
can be used to switch the free layer of MTJs incorporating GeSbTe (20 mW/mum
²
without GeSbTe). The dependence of the power required to switch the MTJs is studied with respect to sample area, pulse duration, and GeSbTe thickness