Spin injection in silicon at zero magnetic field

Grenet, Louis; Jamet, M.; Noé, Pierre; Calvo, V.; Hartmann, J.-M.; Nistor, Lavinia; Rodmacq, B.; Auffret, S.; Warin, P.; Samson, Y.

doi:10.1063/1.3064135

Cited by 55 publications

(61 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recently, methods for spin injection and/or detection in silicon (Si) were explored intensely [2,3,4,5,6,7] because Si has a long spin relaxation time and is compatible with the current industrial semiconductor technologies. Although electrical detections of spin transport in Si conduction channels were demonstrated by two research groups, [4,5] an insulating Al 2 O 3 tunnel barrier between FM and Si was utilized for efficient spin injection and/or detection.…”

Section: Pacs Numbersmentioning

confidence: 99%

Electrical injection and detection of spin-polarized electrons in silicon through an Fe3Si/Si Schottky tunnel barrier

Ando

Hamaya

Kasahara

et al. 2009

Applied Physics Letters

133

112

View full text Add to dashboard Cite

We demonstrate electrical injection and detection of spin-polarized electrons in silicon (Si) using epitaxially grown Fe3Si/Si Schottky-tunnel-barrier contacts. By an insertion of a δ-doped n + -Si layer (∼ 10 19 cm −3 ) near the interface between a ferromagnetic Fe3Si contact and a Si channel (∼ 10 15 cm −3 ), we achieve a marked enhancement in the tunnel conductance for reverse-bias characteristics of the Fe3Si/Si Schottky diodes. Using laterally fabricated four-probe geometries with the modified Fe3Si/Si contacts, we detect nonlocal output signals which originate from the spin accumulation in a Si channel at low temperatures. PACS numbers:To solve critical issues caused by the scaling limit of complementary metal-oxide-semiconductor (CMOS) technologies, spin-based electronics (spintronics) has been studied.[1] For semiconductor spintronic applications, an electrical spin injection from a ferromagnet (FM) into a semiconductor (SC) and its detection are crucial techniques.Recently, methods for spin injection and/or detection in silicon (Si) were explored intensely [2,3,4,5,6,7] because Si has a long spin relaxation time and is compatible with the current industrial semiconductor technologies. Although electrical detections of spin transport in Si conduction channels were demonstrated by two research groups, [4,5] an insulating Al 2 O 3 tunnel barrier between FM and Si was utilized for efficient spin injection and/or detection. To realize gate-tunable spin devices, e.g., spin metal-oxidesemiconductor field effect transistors (spin MOSFET), [8] demonstrations of electrical spin injection and detection in Si conduction channels using Schottky tunnel-barrier contacts will become considerably important. [9,10] By low-temperature molecular beam epitaxy (LTMBE), we recently demonstrated highly epitaxial growth of a binary Heusler alloy Fe 3 Si on Si and obtained an atomically abrupt heterointerface. [11] In this letter, inserting a heavily doped n + -Si layer near the abrupt interface between Fe 3 Si and n-Si, we achieve an effective Shottky tunnel barrier for spin injection into Si. Using nonlocal signal measurements, we demonstrate electrical injection and detection of spin-polarized electrons in Si conduction channels though the Schottky-tunnel-barrier contacts.The n + -Si layer was formed on n-Si(111) (n ∼ 4.5 × 10 15 cm −3 ) by a combination of the Si solid-phase epitaxy with an Sb δ-doping process, [12] where the carrier * E-mail: hamaya@ed.kyushu-u.ac.jp † E-mail: miyao@ed.kyushu-u.ac.jp concentration of the n + -Si layer was ∼ 2.3 × 10 19 cm −3 , determined by Hall effect measurements, and ∼ 10-nmthick non-doped Si layer was grown on the Sb δ-doped layer. Ferromagnetic Fe 3 Si layers with a thickness of ∼ 50 nm were grown by LTMBE at 130 • C, as shown in our previous work.[11] The interface between Fe 3 Si and n + -Si was comparable to that shown in Ref. 11. To evaluate electrical properties of the Fe 3 Si/Si Schottky contacts, we firstly fabricated two different Schottky diodes (∼ 1 mm in diameter) with and w...

show abstract

Section: Pacs Numbersmentioning

confidence: 99%

Electrical injection and detection of spin-polarized electrons in silicon through an Fe3Si/Si Schottky tunnel barrier

Ando

Hamaya

Kasahara

et al. 2009

Applied Physics Letters

133

112

View full text Add to dashboard Cite

show abstract

“…More recently, Höpfner et al obtained 3% of emitted light helicity at remanence using an (Fe/Tb)/MgO tunnel barrier as perpendicular spin injector and using InGaAs quantum dots as the active layer. Experiments performed on Si devices using a (Co/Pt)/Al 2 O 3 spin injector 19 show clear hysteretic cycles of 1.2% amplitude.…”

Section: Introductionmentioning

confidence: 99%

“…[5][6][7] Various experiments have been performed to detect by electrical (e.g., the electrical Hanle effect) or by optical means a spin-polarized current injected from a ferromagnetic reservoir into a III-V semiconductor through an Al 2 O 3 barrier, [8][9][10][11][12] through MgO, [12][13][14][15][16] and through GaO, 17 or into Si through Al 2 O 3 (Refs. [18][19][20][21][22] and SiO 2 (Refs. [23][24][25] as well as into Ge through MgO.…”

Section: Introductionmentioning

confidence: 99%

“…[23][24][25] as well as into Ge through MgO. [26][27][28][29][30][31][32][33][34] Among the latest experiments, the transformation of a spin-polarized electron current into left-or righthanded circularly polarized light in a spin light-emitting diode (spin LED) integrating a III-V semiconductor heterostructure 8,11,[13][14][15][16][17]19,23,34,35 is one of the most striking physical phenomena. The electric dipolar selection rules involved in a quantum well 36 (QW) embedded in a spin LED during electron-hole recombination require spin injection with an out-of-plane magnetization.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Spin injection at remanence into III-V spin light-emitting diodes using (Co/Pt) ferromagnetic injectors

et al. 2012

View full text Add to dashboard Cite

We have studied the perpendicular magnetic anisotropy of Co/Pt multilayers and the electron spin injection efficiency by optical spectroscopy from a [Co(0.6 nm)/Pt(1 nm)] 4 /Fe(0.3 nm)/MgO perpendicular tunnel spin injector grown on AlGaAs/GaAs semiconductor light-emitting diodes. We observe a 2.5% circular polarization at low temperature close to the magnetic remanence when the 0.3 nm Fe film of the ferromagnetic injector is sufficiently thin to maintain the magnetization out of plane. The acquired squared magnetization cycle is explained by the remaining interlayer exchange coupling existing between Fe and the (Co/Pt) multilayer through Pt or possible perpendicular magnetic anisotropy at the MgO/Fe interface. The corresponding spin polarization of the current is then estimated as 7%, measured by photoluminescence techniques, after the necessary uprenormalization, taking into account the electron spin-flip rate in the quantum well. In contrast, no circular polarization is observed when the thin Fe layer is removed and despite the rather high magnetic polarizability of the 5d 9 electronic open shell of Pt at the interface with MgO. This emphasizes the reduced size of tunneling branching of wave functions at the interface, of the order of the atomic plane unit.

show abstract

“…These methods required a large perpendicular magnetic field to overcome the large in-plane shape anisotropy of the FM contact, but later a perpendicular anisotropic magnetic multilayer was shown to allow spin injection into Si at zero external magnetic field [57]. While control samples with non-magnetic injectors do show negligible spin polarization, again no evidence of spin precession was presented, although it is permitted by the geometry [58].…”

Section: Spins In Siliconmentioning

confidence: 96%

Introduction to spin-polarized ballistic hot electron injection and detection in silicon

Appelbaum

2011

Phil. Trans. R. Soc. A.

View full text Add to dashboard Cite

Ballistic hot electron transport overcomes the well-known problems of conductivity and spin lifetime mismatch that plague spin injection attempts in semiconductors using ferromagnetic ohmic contacts. Through the spin dependence of the mean free path in ferromagnetic thin films, it also provides a means for spin detection after transport. Experimental results using these techniques (consisting of spin precession and spin-valve measurements) with silicon-based devices reveals the exceptionally long spin lifetime and high spin coherence induced by drift-dominated transport in the semiconductor. An appropriate quantitative model that accurately simulates the device characteristics for both undoped and doped spin transport channels is described; it can be used to recover the transit-time distribution from precession measurements and determine the spin current velocity, diffusion constant and spin lifetime, constituting a spin 'HaynesShockley' experiment without time-of-flight techniques. A perspective on the future of these methods is offered as a summary.

show abstract

Spin injection in silicon at zero magnetic field

Cited by 55 publications

References 14 publications

Electrical injection and detection of spin-polarized electrons in silicon through an Fe3Si/Si Schottky tunnel barrier

Electrical injection and detection of spin-polarized electrons in silicon through an Fe3Si/Si Schottky tunnel barrier

Spin injection at remanence into III-V spin light-emitting diodes using (Co/Pt) ferromagnetic injectors

Introduction to spin-polarized ballistic hot electron injection and detection in silicon

Contact Info

Product

Resources

About