Spin-dependent resonant tunneling in ZnSe/ZnMnSe heterostructures

Saffarzadeh, Alireza; Bahar, M. K.; Banihasan, M.

doi:10.1016/j.physe.2005.01.015

Cited by 13 publications

(9 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…By employing an additional semimagnetic emitter contact it has been shown theoretically (Egues et al, 2001) that the voltage-dependent magnetoresistance should exhibit robust features like spin split kinks and beating patterns in the case of single barrier and double barrier structures, respectively. The theoretical investigation of asymmetric tunnel structures with differently doped paramagnetic layers reveal high spin filtering effects of up to nearly 100% for suitable magnetic and electric fields in the case of conduction electrons in ZnSe-based structures (Zhai et al, 2003;Zhu and Su, 2004;Papp et al, 2005Papp et al, , 2006Saffarzadeh et al, 2005) as well as for holes and electrons in CdTe/Cd 1−x Mn x Te heterosystems (Malkova and Ekenberg, 2002;Gnanasekar and Navaneethakrishnan, 2006;Lev et al, 2006). Recently, Borza et al (2007) investigated the interesting possibility of an electric field manipulation of the electronic states in a two-partitioned quantum well, which consists of a magnetic and nonmagnetic layer, resulting in the forming of a potential step in the quantum well for one spin component, while the other experiences a deeper well in the magnetic layer region.…”

Section: C3 Paramagnetic Spin-rtdsmentioning

confidence: 99%

Semiconductor spintronics

Fabian¹,

Matos-Abiague²,

Ertler³

et al. 2007

Acta Physica Slovaca. Reviews and Tutorials

915

1,204

View full text Add to dashboard Cite

Spintronics refers commonly to phenomena in which the spin of electrons in a solid state environment plays the determining role. In a more narrow sense spintronics is an emerging research field of electronics: spintronics devices are based on a spin control of electronics, or on an electrical and optical control of spin or magnetism. While metal spintronics has already found its niche in the computer industry-giant magnetoresistance systems are used as hard disk read heads-semiconductor spintronics is yet to demonstrate its full potential. This review presents selected themes of semiconductor spintronics, introducing important concepts in spin transport, spin injection, Silsbee-Johnson spin-charge coupling, and spindependent tunneling, as well as spin relaxation and spin dynamics. The most fundamental spin-dependent interaction in nonmagnetic semiconductors is spin-orbit coupling. Depending on the crystal symmetries of the material, as well as on the structural properties of semiconductor based heterostructures, the spin-orbit coupling takes on different functional forms, giving a nice playground of effective spin-orbit Hamiltonians. The effective Hamiltonians for the most relevant classes of materials and heterostructures are derived here from realistic electronic band structure descriptions. Most semiconductor device systems are still theoretical concepts, waiting for experimental demonstrations. A review of selected proposed, and a few demonstrated devices is presented, with detailed description of two important classes: magnetic resonant tunnel structures and bipolar magnetic diodes and transistors. In view of the importance of ferromagnetic semiconductor materials, a brief discussion of diluted magnetic semiconductors is included. In most cases the presentation is of tutorial style, introducing the essential theoretical formalism at an accessible level, with case-study-like illustrations of actual experimental results, as well as with brief reviews of relevant recent achievements in the field. 72.25.Rb, 75.50.Pp, PACS

show abstract

Section: C3 Paramagnetic Spin-rtdsmentioning

confidence: 99%

Semiconductor spintronics

Fabian¹,

Matos-Abiague²,

Ertler³

et al. 2007

Acta Physica Slovaca. Reviews and Tutorials

915

1,204

View full text Add to dashboard Cite

show abstract

“…with n=1-4. Using the above boundary conditions and the transfer matrix method which connects the incident wave to the transmitted wave [24,29,30], all the reflection and transmission amplitudes can be determined. For the first type of solution, the total transmission coefficient of electrons with energy E and incident angle β = arctan( qy qx ) is given by T (E, β) = |t 1 | 2 , whereas for the second type of solution, the total transmission coefficient is calculated by T (E, β) = 3 i=1 |t i | 2 .…”

Section: Model and Formalismmentioning

confidence: 99%

Surface state transport in double-gated and magnetized topological insulators with hexagonal warping effects

Arabikhah

Saffarzadeh

2019

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

We explore the scattering of Dirac electrons in a double-gated topological insulator in the presence of magnetic proximity effects and warped surface states. It is found that a magnetic field can shift the Dirac cone in momentum space and deform the constant-energy contour, or opens up a band gap at the Dirac point, depending on the magnetization orientation. The double gate voltage induces quantum wells and/or quantum barriers on the surface of topological insulators, generating surface resonant tunnelling states. It is found that the hexagonal warping effect can increase the electronic transport at high energies when the constant-energy contour exhibits a snowflake shape. The energy-dependent conductances in the parallel and antiparallel magnetic configurations exhibit out-of-phase oscillations due to the quantum interference of propagating waves in the region between the two magnetized segments. Although the conductance spectrum of the double-well structure is higher than that of the double-barrier structure, the magnetoresistance ratio versus the separation distance between the two magnetized barriers exhibits pronounced oscillations due to the resonant tunnelling states. We show that the surface state transport can be controlled by the exchange field and gate voltage without breaking time reversal symmetry, suggesting that the double gated and magnetized topological insulators can be utilized to achieve a large magnetoresistance ratio with a tunable sign.

show abstract

“…known for resonant tunneling through double-barrier structures, 35,36 when the incident energy of electrons coincides with the energy of a quasibound state in the quantum well, a resonance condition is fulfilled and the transmission coefficient of the electrons through the heterostructure strongly increases. On the other hand, the position of the quantum well states, formed in the Zn 1−x Mn x Se layer, strongly depends on the well thickness L 2 .…”

Section: -3mentioning

confidence: 99%

Quantum size effects on spin-tunneling time in a magnetic resonant tunneling diode

Saffarzadeh¹,

Daqiq²

2009

Journal of Applied Physics

View full text Add to dashboard Cite

We study theoretically the quantum size effects of a magnetic resonant tunneling diode ͑RTD͒ with a ͑Zn,Mn͒Se dilute magnetic semiconductor layer on the spin-tunneling time and the spin polarization of the electrons. The results show that the spin-tunneling times may oscillate and a great difference between the tunneling time of the electrons with opposite spin directions can be obtained depending on the system parameters. We also study the effect of structural asymmetry which is related to the difference in the thickness of the nonmagnetic layers. It is found that the structural asymmetry can greatly affect the traversal time and the spin polarization of the electrons tunneling through the magnetic RTD. The results indicate that, by choosing suitable values for the thickness of the layers, one can design a high-speed and perfect spin-filter diode.

show abstract

Spin-dependent resonant tunneling in ZnSe/ZnMnSe heterostructures

Cited by 13 publications

References 26 publications

Semiconductor spintronics

Semiconductor spintronics

Surface state transport in double-gated and magnetized topological insulators with hexagonal warping effects

Quantum size effects on spin-tunneling time in a magnetic resonant tunneling diode

Contact Info

Product

Resources

About