Energy spectrum analysis of a realistic single-electron Ga1−xAlxAs/GaAs/Ga1−xAlxAs quantum V-groove in external electric field

Spectral features and optical absorption of vertically stacked V-groove quantum wires

“…From the dimensioning calculations, naturally arises the μ(x Al ) function defined as the ratio between the position-dependent electron's effective mass in Ga 1−x Al x As and in GaAs, that is, μ(x Al ) m * (x Al )/m * (0). Consequently, with this definition, it can be established [34] the effective Bohr radius a * 0 , effective Rydberg Ry * , and the renormalized electric field strength η as units of length, energy, and electric field, respectively, which are defined as a * 0 2 (4π )/m * (0)e 2 , Ry * m * (0)e 4 /2 2 (4π ) 2 , and η eFa * 0 /Ry * . In the present work, we have implemented the relations extensively discussed by [40] describing the electron's effective mass m * (x Al ) in Ga 1−x Al x As and the confinement potential in the GaAs/Ga 1−x Al x As heterojunction, both dependent on the aluminum concentration.…”

“…With all the previous elements composing the system Hamiltonian, the eigenvalue problem on the cross-sectional plane Ĥ⊥ ψ( r ⊥ ) E ⊥ ψ( r ⊥ ) can be firstly solved [34,35] with the aim to solve the three-dimensional problem as will be shown later. The cross-sectional problem can be alternatively obtained [41] from the minimization of the functional:…”

“…Recently, other authors have made important computational efforts to solve the single VGQW problem [19] by using a finite differences method. More recently, an excellent approximation to realistic VGQWs [34,35] by using the finite element method was reported allowing to calculate electronic states [34] and the corresponding nonlinear optical generation [35]. Nevertheless, at this stage, theoretical studies related to vertically stacked V-grooves are really scarce [36].…”

“…Nevertheless, at this stage, theoretical studies related to vertically stacked V-grooves are really scarce [36]. In this article, we study some spectral features of two vertically stacked GaAs/Ga 1−x Al x As VGQWs (with the realistic size/shape described in [34,35]) such as the energy level ordering as a function of the VGQW geometry, and the linear, nonlinear, and total optical absorption. These findings can potentially give some hints to optimally tune the optical response of realistic v-groove superlattices or foster the study of the fundamental physics underlying the development of new optical devices [37][38][39].…”

Self-Consistent Schrödinger-Poisson Study of Electronic Properties of GaAs Quantum Well Wires with Various Cross-Sectional Shapes

“…The beginnings of research on this type of nanosystems date back to the 1980s, with illustrative examples in References [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17], and has continued until the present, with a significant number of experimental and theoretical reports in the literature. Among the most recent works on QWs, we can mention those appearing in References [18][19][20][21][22][23][24][25][26][27][28].…”