In this work, we examine solutions of the system of equations obtained by applying the Noether gauge symmetry (NGS) and its conserved quantity for the standard general relativity (GR) and the non-minimal derivative coupling (NMDC) cosmological model. We discover two salient features of the solutions. The first one is $$a(t)\propto t^{1/3}$$ a ( t ) ∝ t 1 / 3 for a kinetic-dominant phase which may emerge before inflationary period at very early time for GR case. The second one is a new form of scalar field $$\phi (t)$$ ϕ ( t ) govern by the exponential cosmological solution for NMDC case, $$\phi (t)=(c_{1}+c_{2}t)e^{-\lambda t}+c_{3}$$ ϕ ( t ) = ( c 1 + c 2 t ) e - λ t + c 3 .
We propose a coaxial cylindrical quantum well wire which is composed of layers of a dilute magnetic semiconductor (DMS) and a nonmagnetic semiconductor (NMS). Using effective mass approximation, we present a numerical calculation of the eigenenergies and eigenstates of electrons in the heterostructure. The variation of the spin‐dependent energy levels is influenced by the giant Zeeman splitting and potential energies due to a vector potential for sufficiently low and high magnetic fields, respectively. It is found that crossing and anticrossing behaviors of energy levels can be controlled by the thickness of a NMS layer. The ballistic transport of the structure is also investigated. The ranges of the Fermi energy for obtaining full spin polarization are suggested in this work.
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