Determining The Spin Dependent Mean Free Path In Co90fe10 Using Giant Magnetoresistance

The spin dependent mean free path in Co90Fe10 is determined as a function of temperature down to 5 K using two different spin valve structures. At 5 K the spin dependent mean free path for one structure was measured to be 9.4 +/- 1.4 nm, decreasing by a factor of 3 by 350 K. For the other structure, it is 7.5 +/- 0.5 nm at 5 K and decreased by a factor of 1.5 by 350 K. In both cases, the spin dependent mean free path approaches the typical thickness of ferromagnetic layers in spin valves at room temperature and, thus, has an impact on the choice of design parameters for the development of new spintronic devices. (c) 2005 American Institute of Physics.