臺灣博碩士論文加值系統

本文乃針對量子線的結構來做研究。我們分析了在磁場的作用下 , 量子
線中加入雜質其電子能階的種種變化情形。經由理論推導及數值計算的結
果, 顯示出在強、弱不同的磁場影響下, 會出現不同型式的電子能階。例
如強磁場中, 電子能階偏向於量子線內未加入雜質的情形, 其能階的變
化, 隨主量子數的增加而等量遞增; 至於弱磁場中 , 因為庫侖作用相對
的顯得特別重要, 因此系統能階的變化主要由庫侖位勢所決定。另外加入
雜質的多寡, 與量子侷限結構的改變, 對某些能態亦有相當重要的影響。
像本文中所做線性雜質列與量子碟的研究即是。前者是改變雜質與電子間
的庫侖作用力; 而後者則是量子線邊界退化的極限。它們的結果, 在本文
中均有討論。

In this study,we analyze and calculate the eigenenergies'
distribution of the cylindrical-shaped quantum confinement
system, contains various impurities, with finite-potential
barrier under an applied magnetic field. We find that there are
different dependence of the energy level on the magnetic field
strength for the strong and weak magnetic field regimes. For
example, the energy level spectra are close to the them without
any impurity in the strong magnetic field. The differ- ence of
the energy levels increases equally for the increasing
principle quantum number. In the weak magnetic regime, the
energy levels are mainly determined by Coulomb potential
profile because the Coulomb interaction is more significant
compared with the other potentials. By changing the Coulomb
interaction between the impurity and electron, we can calculate
the energy levels of the linear impurity-array quantum wire
eith the analog calculation proce- dures for the single
impurity quantum wire. Similarly, we can also implement the
developed numerical calculation method to the single impurity
quantum disk, which is the special case of a cylindrical
quantum wire with single impurity at origin and with
longitudinal axis approaching to zero.