Effect of Rashba spin-orbit coupling and external magnetic field on electronic minibands in highly strained one-layer quantum ring superlattice Vram Mughnetsyan * , Aram Manaselyan, Albert Kirakosyan Department of Solid State Physics, Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia article info Article history: Received 7 December 2016 Received in revised form 3 February 2017 Accepted 3 February 2017 Available online 6 February 2017 Keywords: Quantum ring superlattice Spin-orbit interaction Elastic strain Magnetic field Energy dispersion abstract The Rashba spin-orbit coupling for electronic states in a strained one layer superlattice, composed of InAs/GaAs quantum rings has been investigated in the presence of uniform magnetic field directed perpendicular to the lattice plane. The dispersion surfaces and the energy dependencies on the magnetic field induction are obtained by the exact diago- nalization procedure using the Fourier transformation to the momentum space. The characteristic splitting of the mini-bands as well as the crossings of the dispersion surfaces at the high symmetry points in the Brillouin zone have been observed. An upward shift of the minibands by about 60 meV due to strain in superlattice has been observed. © 2017 Elsevier Ltd. All rights reserved. 1. Introduction Quantum dots (QD) and quantum rings (QR) containing few interacting electrons have received considerable attention for over a decade because of the rich physics they exhibit [1,2]. Just as the QDs, QRs are also nanometer-sized structures that confine electrons in all three directions. Aharonov-Bohm oscillations [3] and the persistent current [4] have been observed recently in small conducting rings. On the other hand the possibility of the experimental realization of QRs with only a few electrons have been demonstrated in Refs. [5] and [6]. So the experimental study of QRs properties as well as the development of the many-particle theory in QRs is of great interest [7e9]. QRs are of particular interest due to their unique electronic, magnetic, and optical properties [10e12]. In most cases, these structures are fabricated with an intrinsic elastic strain field arising from the lattice mismatch be- tween the QR (QD) and matrix materials [13]. Knowledge of this strain field is crucial for further device modeling since the strain substantially modifies the electronic band structure which, in turn, strongly effects on the performance of optoelec- tronic devices [14,15]. The introduction of strain may provide a facile way to fabricate from mid-wavelength to long- wavelength multi-color infrared detectors via InAs or InGaAs QDs capped by GaAs, InGaAs, InP, or GaInP [16]. On the other hand the inhomogeneous strain relaxation in strained quantum structures can be utilized to fabricate QRs [10]. Recently impressive progress has been made in the field of manufacturing of ordered structures composed of two or three dimensional arrays of QRs [17e19]. For example, stacked layers of self-assembled InGaAs/GaAs quantum rings have been * Corresponding author. E-mail addresses: vram@ysu.am (V. Mughnetsyan), amanasel@ysu.am (A. Manaselyan), kirakosyan@ysu.am (A. Kirakosyan). Contents lists available at ScienceDirect Superlattices and Microstructures journal homepage: www.elsevier.com/locate/superlattices http://dx.doi.org/10.1016/j.spmi.2017.02.001 0749-6036/© 2017 Elsevier Ltd. All rights reserved. Superlattices and Microstructures 104 (2017) 10e18