Efficient nonlinear room-temperature spin injection from ferromagnets into semiconductors through a modified Schottky barrier

Abstract

We suggest a consistent microscopic theory of spin injection from a ferromagnet (FM) into a semiconductor (S). It describes tunneling and emission of electrons through modified FM-S Schottky barrier with an ultrathin heavily doped interfacial S layer . We calculate nonlinear spin-selective properties of such a reverse-biased FM-S junction, its nonlinear I-V characteristic, current saturation, and spin accumulation in S. We show that the spin polarization of current, spin density, and penetration length increase with the total current until saturation. We find conditions for most efficient spin injection, which are opposite to the results of previous works, since the present theory suggests using a lightly doped resistive semiconductor. It is shown that the maximal spin polarizations of current and electrons (spin accumulation) can approach 100% at room temperatures and low current density in a nondegenerate high-resistance semiconductor.

7 pages, 2 figures; provides detailed comparison with earlier works on spin injection

References in corpus (2)

• A class of spin injection-precession ultrafast nanodevices
• High-frequency spin valve effect in ferromagnet-semiconductor-ferromagnet structure based on precession of injected spins

Cited by in corpus (12)

• Spin dynamics in semiconductors
• Spin Injection and Relaxation in Ferromagnet-Semiconductor Heterostructures
• Spin dynamics in a compound semiconductor spintronic structure with a Schottky barrier
• Spin transport theory in ferromagnet/semiconductor systems with non-collinear magnetization configurations
• Modeling for Semiconductor Spintronics
• Spin accumulation in degenerate semiconductors near modified Schottky contact with ferromagnets
• Spin diffusion/transport in $n$-type GaAs quantum wells
• Schottky-barrier induced spin dephasing in spin injection
• Complete spin polarization of electrons in semiconductor layers and quantum dots
• Highly polarized injection luminescence in forward-biased ferromagnetic-semiconductor junctions at low spin polarization of current
• Energy-efficient hybrid spintronic-straintronic reconfigurable bit comparator
• Electrical expression of spin accumulation in ferromagnet/semiconductor structures