On the control of optical spin injection by tuning the band gap offset in magnetic/non-magnetic hybrid structure

The gate controllable SOI provides useful information about spin interference.1 Spin interference effects are studied in two different interference loop structures. It is known that sample specific conductance fluctuations affect the conductance in the interference loop. By using array of many interference loops, we carefully pick up TRS Altshuler-Aronov-Spivak (AAS)-type oscillation which is not sample specific and depends on the spin phase. The experimentally obtained gate voltage dependence of AAS oscillations indicates that the spin precession angle can be controlled by the gate voltage.2 We demonstrate the time reversal Aharonov-Casher (AC) effect in small arrays of mesoscopic rings.3 By using an electrostatic gate we can control the spin precession angle rate and follow the AC phase over several interference periods. We also see the second harmonic of the AC interference, oscillating with half the period. The spin interference is still visible after more than 20π precession angle. We have proposed a Stern-Gerlach type spin filter based on the Rashba SOI.4 A spatial gradient of effective magnetic field due to the nonuniform SOI separates spin up and down electrons. This spin filter works even without any external magnetic fields and ferromagnetic contacts. We show the semiconductor/ferromagnet hybrid structure is an effective way to detect magnetization process of submicron magnets. The problem of the spin injection from ferromagnetic contact into 2DEG is also disicussed. Note from Publisher: This article contains the abstract only.

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Spin injection due to interfacial spin asymmetry in a ferromagnet-semiconductor hybrid structure

Journal of Applied Physics ◽

10.1063/1.2801097 ◽

2007 ◽

Vol 102 (8) ◽

pp. 084310 ◽

Cited By ~ 4

Author(s):

S. Bala Kumar ◽

S. G. Tan ◽

M. B. A. Jalil ◽

Yong Jiang

Keyword(s):

Spin Asymmetry ◽

Spin Injection ◽

Hybrid Structure

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Spin injection with Fe/InAs hybrid structure

Compound Semiconductors 2001 ◽

10.1201/9781482268980-46 ◽

2002 ◽

pp. 307-320

Keyword(s):

Spin Injection ◽

Hybrid Structure

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SPIN INJECTION INTO TWO-DIMENSIONAL ELECTRON GAS THROUGH A SPIN-FILTERING INJECTOR

Modern Physics Letters B ◽

10.1142/s0217984908016273 ◽

2008 ◽

Vol 22 (16) ◽

pp. 1535-1545

Author(s):

Y. WANG ◽

A. P. LIU ◽

J. BAO ◽

X. G. XU ◽

Y. JIANG

Keyword(s):

Spin Polarization ◽

Spin Injection ◽

Electron Gas ◽

Hybrid Structure ◽

Two Dimensional ◽

Dimensional Electron ◽

Two Dimensional Electron Gas ◽

Tunneling Model ◽

Dimensional Electron Gas ◽

Spin Filtering

In this paper, large spin polarization and magnetoconductance in a ferromagnet (FM)/ferromagnetic insulator (FI)/two-dimensional electron gas (2DEG)/non-magnetic insulator (I)/FM hybrid structure are theoretically predicted by introducing a spin-filtering injector. In the framework of coherent tunneling model, the electron transmission probability, spin polarization and magnetoconductance in the hybrid structure all oscillate with the electron density within the 2DEG channel. A complete single-mode spin injection would be realized by designing a well-defined geometry to adjust the competition between the spin-dependent tunneling of the conductive electrons and spin-filtering effect of the FI barrier.

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Ultralow-frequency band gap in a quasi-zero-stiffness multi-resonator periodic hybrid structure

Wave Motion ◽

10.1016/j.wavemoti.2021.102825 ◽

2021 ◽

pp. 102825

Author(s):

Buliang Xie ◽

Meiping Sheng

Keyword(s):

Band Gap ◽

Frequency Band ◽

Hybrid Structure ◽

Ultralow Frequency

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First-principles study on electronic properties of stanene/WS2 monolayer

Modern Physics Letters B ◽

10.1142/s0217984917502712 ◽

2017 ◽

Vol 31 (29) ◽

pp. 1750271 ◽

Cited By ~ 3

Author(s):

Xi Chen ◽

Yin Li ◽

Jia Tang ◽

Liyuan Wu ◽

Dan Liang ◽

...

Keyword(s):

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Hybrid Structure ◽

Interlayer Distance ◽

Electron Effective Mass ◽

High Carrier Mobility ◽

The Difference ◽

The Stability ◽

Finite Band

We present first-principles calculations to study the stability and electronic properties of stanene on WS2 hybrid structure. It can be seen that the stanene is bound to WS2 substrate with an interlayer distance of about 3.0 Å with a binding energy of −51.8 meV per Sn atom, suggesting a weak interaction between stanene and WS2. The nearly linear band dispersion character of stanene can be preserved with a sizeable band gap in stanene on WS2 hybrid structure due to the difference of onsite energy induced by WS2 substrate, which is more helpful to the on–off current ratio in the logical devices made of stanene/WS2. Moreover, the band gaps, the position of Dirac point with respect to Fermi level, and electron effective mass (EEM) of stanene on WS2 hybrid structure can be tuned by the interlayer distance, external electric field and strains. These results indicate that stanene on WS2 hybrid structure is a promising candidate for stanene-based field-effect transistor (FET) with a finite band gap and high carrier mobility.

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Temperature dependence of spin injection efficiency in an epitaxially grown Fe/GaAs hybrid structure

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2009.07.037 ◽

2009 ◽

Vol 321 (22) ◽

pp. 3795-3798 ◽

Cited By ~ 4

Author(s):

Tae Hwan Lee ◽

Hyun Cheol Koo ◽

Kyung Ho Kim ◽

Hyung-jun Kim ◽

Joonyeon Chang ◽

...

Keyword(s):

Temperature Dependence ◽

Spin Injection ◽

Hybrid Structure ◽

Injection Efficiency

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TEM and cathodoluminescence of precipitates in II-VI semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104509 ◽

1988 ◽

Vol 46 ◽

pp. 488-489

Author(s):

Joanna L. Batstone

Keyword(s):

Crystal Growth ◽

Band Gap ◽

Local Strain ◽

Wide Band ◽

Optoelectronic Device ◽

Wide Band Gap ◽

Bulk Crystal Growth ◽

Transmission Electron ◽

Device Applications ◽

Stoichiometry Control

Interest in II-VI semiconductors centres around optoelectronic device applications. The wide band gap II-VI semiconductors such as ZnS, ZnSe and ZnTe have been used in lasers and electroluminescent displays yielding room temperature blue luminescence. The narrow gap II-VI semiconductors such as CdTe and HgxCd1-x Te are currently used for infrared detectors, where the band gap can be varied continuously by changing the alloy composition x.Two major sources of precipitation can be identified in II-VI materials; (i) dopant introduction leading to local variations in concentration and subsequent precipitation and (ii) Te precipitation in ZnTe, CdTe and HgCdTe due to native point defects which arise from problems associated with stoichiometry control during crystal growth. Precipitation is observed in both bulk crystal growth and epitaxial growth and is frequently associated with segregation and precipitation at dislocations and grain boundaries. Precipitation has been observed using transmission electron microscopy (TEM) which is sensitive to local strain fields around inclusions.

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Structural properties of GaAs/InGaAs/GaAs (001) and InGaAs/GaAs (001) heterostructures and correlation with electronic properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176149 ◽

1990 ◽

Vol 48 (4) ◽

pp. 602-603

Author(s):

J.M. Bonar ◽

R. Hull ◽

R. Malik ◽

R. Ryan ◽

J.F. Walker

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Gaas Substrate ◽

Critical Thickness ◽

Lattice Mismatch ◽

Band Offset ◽

Misfit Dislocations ◽

Gaas Substrates ◽

Gaas Structure ◽

Low X

In this study we have examined a series of strained heteropeitaxial GaAs/InGaAs/GaAs and InGaAs/GaAs structures, both on (001) GaAs substrates. These heterostructures are potentially very interesting from a device standpoint because of improved band gap properties (InAs has a much smaller band gap than GaAs so there is a large band offset at the InGaAs/GaAs interface), and because of the much higher mobility of InAs. However, there is a 7.2% lattice mismatch between InAs and GaAs, so an InxGa1-xAs layer in a GaAs structure with even relatively low x will have a large amount of strain, and misfit dislocations are expected to form above some critical thickness. We attempt here to correlate the effect of misfit dislocations on the electronic properties of this material.The samples we examined consisted of 200Å InxGa1-xAs layered in a hetero-junction bipolar transistor (HBT) structure (InxGa1-xAs on top of a (001) GaAs buffer, followed by more GaAs, then a layer of AlGaAs and a GaAs cap), and a series consisting of a 200Å layer of InxGa1-xAs on a (001) GaAs substrate.

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