Highly polarized emission in spin resolved photoelectron spectroscopy of α-Fe(001)/GaAs(001)

Interface Magnetism in Ferromagnetic Metal–compound Semiconductor Hybrid Structures

“…Utilizing the element specificity of XMCD, the orbital-and spin-components of the Fe magnetic moments were extracted, demonstrating a bulk-like value for the Fe spin magnetic moment and a large enhancement in the orbital magnetic moment due to the reduced symmetry at the interface. (Bulk-like Fe magnetic moments at the Fe/GaAs(001) interface were later theoretically predicted by calculations of Demchenko and Liu 91 , and Tobin et al have used spin-resolved photoelectron spectroscopy to also reveal bulk-like magnetism at the Fe/GaAs(001) interface, despite significant intermixing 74 . )…”

“…Once back under vacuum, the wafer is heated in order to thermally desorb the As passivation, leaving a clean semiconductor surface on which to deposit metal 48,66,74 : desorption of the As passivation typically occurs at temperatures in the region of 450 • C. This method of obtaining a clean III-V surface is particularly common where sputter-deposition of the ferromagnetic metal is employed 34,56,75,76 : as these types of deposition system generally lack surface analysis tools, little is known regarding the phase of the surface reconstructions achieved. Further surface treatment may also be applied, typically in the form of an in-situ thermal anneal of the As-desorbed wafer.…”

Growth, structure and morphology of epitaxial Fe(0 0 1) films on GaAs(0 0 1)c(4 × 4)

“…The deposition of highly spin-polarized ferromagnetic layers on semiconductor substrates is essential for the fabrication of efficient spin-injectors for spintronic [1] and magnetoelectronic devices [2]. With a high Curie temperature of 770 • C for bulk Fe and a spin polarization of the conduction electrons of 42% [3,4], Fe epilayers on GaAs(0 0 1) have become a model system for spin-injection into semiconductors [5][6][7][8][9][10][11]. Electrical spin injection at 4.5 K into a GaAs quantum well from an Fe/AlGaAs Schottky contact yielded a spin polarization as high as 32% [8].…”

“…Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. 4 Upper Austria University of Applied Sciences, Stelzhamerstraße 23, 4600 Wels, Austria films have been obtained irrespective of the reconstruction or composition (As-rich or Ga-rich) of the GaAs(0 0 1) surface at growth temperatures between −150 and +300 • C [13][14][15][16][17][18][19][20][21][22][23][24][25][26]. For Fe[1 0 0] GaAs[1 0 0], where four Fe atoms sit in one GaAs(0 0 1) unit cell, thus occupying different lattice sites, the misfit is calculated to 1.38% (a GaAs = 0.5653 nm, 2a Fe = 0.5732 nm).…”

Stress and interdiffusion during molecular beam epitaxy of Fe on As-rich GaAs(001)

“…(Some figures in this article are in colour only in the electronic version) Due to the high Curie temperature of Fe well above room temperature (770 • C), a spin polarization of 42% of its conducting electrons [1,2], its relatively low misfit of 1.38% with respect to GaAs(001) as well as the ease of fabrication, epitaxial Fe/GaAs(001) hybrid structures have evolved to a model system for spin-injection into semiconductors [3][4][5][6][7][8][9].…”