Studies on the Coherence Time of the Electron Weakly Coupled with Phonons in Asymmetrical Semi-exponential Quantum Well by Employing Linear Combination Operation Method

Abstract

We investigate theoretically the properties of the coherence time of a symmetric semi-exponential quantum well qubit using the linear combination operator method for the first time. We derive the influences of quantum well barrier height and the range of an asymmetrical semi-exponential confinement potential (ASECP) on the vibration frequency, first excited-state (FES) energy, excitation energy and coherence time using unitary transformations and Fermi’s Golden Rule. We find that the vibration frequency, FES energy and excitation energy are increasing functions of the barrier height, but are decreasing ones of the ASECP range; the coherence time, however, has totally opposite properties. Our results may be useful for the design and implementation of solid-state quantum computation.