Magneto‐transport in single InGaAs quantum wells of different shapes

Abstract

Key words In x Ga 1-x As/In y Al 1-y As QW, magneto-transport, Shubnikov-de Haas oscillations. PACS 73.40 HmThe magneto-transport measurements in InGaAs/InAlAs quantum wells (QW) obtained b y MOCVD technology on InP substrates, and known as High Electron Mobility Transistors, were performed at low temperatures of 0.4 -15 K and high magnetic fields up to 10 T (with the magnetic field induction B perpendicular to the plane of the well). Three kinds of structures were studied. The Shubnikov-de Haas oscillations demonstrating the occupancy of two subbands were observed. In order to determine the energies of Landau levels in the QW subbands, we have used the Zawadzki-Pfeffer quazi-two-band model. Good agreement between calculated Landau levels and Fermi level from one hand, and positions of the Shubnikovde Haas oscillations peaks from the other, enable us to determine the parameters of 2D electron gas in QW: effective mass and carrier density.

Magnetospectroscopy of symmetric and anti-symmetric states in double quantum wells

“…5a). It is important to mention that no beating-effect was observed in case of the structure with single QW based on the same heterostructures In 0.65 Ga 0.35 As/In 0.52 Al 0.48 As [24].…”

“…The method of producing the structures with a single QW, which was reported earlier [23,24], was used also for producing DQW structure with rectangular, as well as triangular QWs. The structure of the first type (#2506) consists of two In 0.65 Ga 0.…”

“…The calculations of the LL's for the sample #2506I were performed using the band parameters, determined previously for the sample with the single quasi-rectangular QW [24]. These parameters are listed in Table 2, they are the same for both of the samples.…”

Parallel magnetotransport in multiple quantum well structures

“…We adapted Zawadzki-Pfeffer quazi-two-band model [10,11] for calculation of the Landau level energies in subbands of QW. The description of the adapted model for the different shape QW is presented in [8].…”

“…These methods must be verified on real QW's. The detail description of the engineering of structures as well as describing of the experimental data and their interpretation are presented in original articles [7,8]. Here we present the main results only.…”