Electronic properties and transition processes in semiconductor quantum box structures and artificially localized states (super-donors)

对于人工定域态，即在磁场中由量子阱组成的磁量子箱（Mag-QB）体系，在杂质层形成的库伦量子箱（Imp-QB）体系，在量子阱中形成的库伦量子箱（Imp-QB）体系，以及通过纳米加工技术形成的量子箱（Fab-QB），我们研究了以下三个主题。首先，我们观察了超晶格中的纵向磁声子共振，磁场下三势垒隧道二极管中通过朗道能级的隧穿过程，以及双势垒隧道二极管中通过供体能级的二维(2D) -0D-2D隧穿过程。此外，我们在电子束制造的QB中观察到旋转门运动和光子辅助隧穿。我们还制作了自组装的InAs量子盒并进行了输运测量。其次，我们研究了超供体能级的能量松弛，以便从理论上和实验上澄清声子瓶颈的存在。我们的理论表明，由于声子散射的抑制，一维耦合量子盒结构中存在声子瓶颈和布洛赫振荡。然而，在与光学和声学散射相关的共振中，在几个meV内相对快速衰减的可能性被证明。实验结果表明，磁场下三势垒共振隧道结构的输运性质和量子阱中电子-空穴系统的快速弛豫过程的光学分析都表明了快速弛豫过程的存在。第三，对于超给体态的光子激发和电离，我们通过在（311）A量子阱中引入Si受体，研究了给体能级的可控性、电导率的温度依赖性和红外响应。

As for artificially localized states, namely, the magnetic quantum box (Mag-QB) systems consisteing of quantum wells at magnetic fields, Coulomb quantum box (Imp-QB) systems formed at impurity, levels in quantum wells, and quantum boxes by nanofabrication technique (Fab-QB), we have studied following three subjects.First, we observed longitudinal magnetophonon resonances in superlattices, tunnelling processes through Landau levels in triple barrier tunnel diodes at magnetic fields, and two-dimension (2D) -0D-2D tunnelling through donor levels in double barrier tunnel diodes. In addition, we observed turnstile motion and photon-assisted tunnelling in an electron-beam-fabricated QB.We also fabricated self-assembled InAs quantum boxes and carried out transport measurements.Second, we examined energy relaxation in super-donor levels in order to clarify presence of phonon bottle-neck both theoretically and experimentally. Our theory showed existence of phonon bottle-neck, and Bloch oscillations in 1D coupled quantum box structures due to suppression of phonon scattering. However, the possibility of relatively fast decay within a few meV at resonance relating to both optical and accoustical scatterings were demonstrated. Experimentally, both transport properties of a triple barrier resonant tunnel structure at magnetic fields and optical analysis of a fast relaxation process in electron-hole systems in quantum wells at magnetic fields suggested presence of fast relaxation process.Third, as for photon excitation and ionization of super-donor states, we investigated controllability of donor levels, temperature dependences of conductivity, and infrared response by introducing Si acceptors in (311) A quantum wells.