37 research outputs found
Optically pumped intersubband laser: Resonance positions and many-body effects
NRC publication: Ye
Effect of emitter design on the dc characteristics of InP-based double-heterojunction bipolar transistors
NRC publication: Ye
Crossing and anticrossing of spin-split Landau levels in an AlGaAs/GaAs parabolic quantum well
NRC publication: Ye
Quantum and transport mobilities in an AlGaAs/GaAs parabolic quantum-well structure
NRC publication: Ye
Hanle measurements of electrodeposited Fe/GaAs spin tunnel contacts
We report spin transport in electrodeposited Fe/n-GaAs tunnel diodes via three-terminal Hanle measurements. For temperatures between 20K and 150K, the spin resistance was up to 20 times higher than expected from theoretical calculations and 1000 times larger compared to a vacuum-deposited counterpart. This higher spin resistance was correlated with a higher contact resistance, and a higher concentration of oxygen impurities in the electrodeposited Fe film and interface, as detected via x-ray photoelectron and Auger spectroscopies, and inferred from Fe film nucleation rates. These results can be explained via a small effective tunnel-contact area of 5%, but extra spin filtering via interfacial states or magnetic oxide layers cannot be ruled out. The spin diffusion times (8.5 \ub1 0.4ns to 1.8 \ub1 0.4ns, for 20K to 150K) extracted from Lorentzian fits were in good agreement with values obtained from earlier 4-terminal Hanle measurements (7.8 \ub1 0.4ns to 3.2 \ub1 0.4ns, for 25K to 77K), both 10 times slower than reported vacuum-deposited contacts.Peer reviewed: YesNRC publication: Ye