**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**30075

##### Behavior of Current in a Semiconductor Nanostructure under Influence of Embedded Quantum Dots

**Authors:**
H. Paredes Gutiérrez,
S. T. Pérez-Merchancano

**Abstract:**

Motivated by recent experimental and theoretical developments, we investigate the influence of embedded quantum dot (EQD) of different geometries (lens, ring and pyramidal) in a double barrier heterostructure (DBH). We work with a general theory of quantum transport that accounts the tight-binding model for the spin dependent resonant tunneling in a semiconductor nanostructure, and Rashba spin orbital to study the spin orbit coupling. In this context, we use the second quantization theory for Rashba effect and the standard Green functions method. We calculate the current density as a function of the voltage without and in the presence of quantum dots. In the second case, we considered the size and shape of the quantum dot, and in the two cases, we worked considering the spin polarization affected by external electric fields. We found that the EQD generates significant changes in current when we consider different morphologies of EQD, as those described above. The first thing shown is that the current decreases significantly, such as the geometry of EQD is changed, prevailing the geometrical confinement. Likewise, we see that the current density decreases when the voltage is increased, showing that the quantum system studied here is more efficient when the morphology of the quantum dot changes.

**Keywords:**
Quantum semiconductors,
nanostructures,
quantum dots,
spin polarization.

**Digital Object Identifier (DOI):**
doi.org/10.5281/zenodo.1129127

**References:**

[1] D.Z.-Y. Ting, X. Cartoixà. “InAs/GaSb/AlSb Resonant Tunneling Spin Device Concepts”, Physica E 20, pp. 350 – 354 (2004).

[2] Sun, Wang, and Guo. “Quantum transport theory for nanostructures with Rashba spin-orbital interaction”, Phys. Rev B 71, 165310, 2005.

[3] T. Noda, N. Koguchi. “Current–voltage characteristics in double-barrier resonant tunneling diodes with embedded GaAs quantum rings”, Physica E 32, pp 550–553 (2006).

[4] K. Gnanasekar, K. Navaneethakrishnan. “Effects of Rashba spin–orbit interaction on spin-dependent resonant tunneling in ZnSe/Zn1−xMnxSe multilayer heterostructures”, Physica E 35, pp. 103–109 (2006).

[5] Ernie Pan, Yu Zou, Peter W. Chung, and Yan Zhang. “Interlayer correlation of embedded quantum-dot arrays through their surface strain energy distributions”, Phys. Rev. B 80, 073302 (2009).

[6] C. M. Ryu and S. Y. Cho, “Phase evolution of the transmission coefficient in Aharonov-Bohm ring with Fano resonance” Phys. Rev. B 58, 3572 (1998).

[7] S. Murakami, N. Nagaosa, and S. C. Zhang, “Dissipationless quantum spin current at room temperature” Science 301, 1348 (2003).

[8] J Sinova, D. Culcer, Q Niu, N. A. Sinitsyn, T. Jungwirth, and A. H. MacDonald, “Universal intrinsic spin Hall effect” Phys. Rev. Lett. 92, 126603 (2004).

[9] B. K. Nikolic, L. P. Zarbo, and S. Souma, "Spin currents in semiconductor nanostructures: A nonequilibrium Green function approach," Chapter 24, pp 814–866 in Volume I of "The Oxford Handbook on Nanoscience and Technology: Frontiers and Advances," Eds. A. V. Narlikar and Y. Y. Fu.

[10] A.V. Narlikar, Y. Y. Fu Oxford “Handbook of Nanoscience and Technology: Vol I-III Oxford University Press, pp 2 814-866, 2010.

[11] S.M. Mirzanian, A.A. Shokri. “Angular dependence of shot noise in the presence of Rashba spin–orbit coupling in semiconductor spintronics junctions”, Physica E 54, pp 59–64 (2013).

[12] N. Niketić et al. “Properties of the resonant tunneling diode in external magnetic field with inclusion of the Rashba effect”, Solid State Communications 189, pp 52–57 (2014).

[13] L. V. Keldysh, “Diagram technique for nonequilibrium processes”, Sov. Phys. JETP 20, 1018 (1965).

[14] J. H. Marin, I. D. Mikhailov and L. F García, “Charge distribution in quantum dot with trapped exciton”, Physica B 398 (2007), pp 135-143.

[15] D. S. Smirnov, M. M. Glazov, E. L. Ivchenko, and L. Lanco. “Theory of optical spin control in quantum dot microcavities”, Phys. Rev. B 92, 115305 (2015).

[16] Leonor Chico, A. Latge, and Luis Brey. “Symmetries of quantum transport with Rashba spin–orbit: graphene spintronics”, Phys. Chem. Chem. Phys., 17, pp. 16469-16475. 2015.

[17] Ichiro Tanaka, Y. Tada, S. Nakatani, K. Unoa, I. Kamiya, H. Sakaki. “Resonant tunneling of electrons through single self-assembled InAs quantum dot studied by conductive atomic force microscopy”, Physica E 42 pp 2606–2609 (2010).