Quantum-confined hydrogenic impurity in a spherical quantum dot under the influence of parallel electric and magnetic fields

A recently developed computational technique, the complex absorbing potential (CAP) method for locating complex poles of resonance states, is applied to calculate the field-induced energy shifts and widths of the ground stale of a hydrogenic donor in a quantum dot (QD) subjected to parallel electric and magnetic fields. The present model demonstrates that resonances in a confined hydrogen atom lead to an anomalous behaviour due to the quantum confinement of the atom. We have studied the influence of magnetic field on the quantum-confined Stark effect. With increasing magnetic field, resonances shift to higher level and the width gets narrower with less impact on the oscillation amplitude. We will discuss our results in terms of a QD system realized in the GaAs/Ga1−xAlxAs sample.