用全量子理论导出隧穿量子点分子-辐射场相互作用系统状态满足的微分方程组,在相干态辐射场和量子点分子处于隧穿激发态及基态的初始条件下,应用Pegg-Barnett相位理论计算和分析了辐射场的相位概率分布及相位涨落,研究了声子-量子点分子作用对辐射场相位的影响,并与Husimi相位分布做了比较.结果表明,温度显著影响光场相位概率分布的时间演化规律,声子既可以抑制也可以增强辐射场相位扩散和涨落,取决于量子点分子的初态.Husimi相位分布和Pegg-Barnett相位分布符合度相当高.
A full quantum theory is adopted to derive the differential equations satisfied by the state of a system that is composed of an electron tunneling-coupled quantum-dot molecule interacting with a single-mode radiation field. The phase of the field is calculated by the Pegg-Barnett quantum phase formalism under the initial condition of a coherent-state field and the tunneling excited state or ground state for the quantum-dot molecule. Phase distribution and fluctuation of the field are analyzed, the influence of interaction between phonons and the quantum-dot molecule on the Pegg-Barnett quantum phase is investigated, and the phase distribution is compared with the Husimi phase distribution of the field. Results indicate that temperature can have a marked impact on the phase evolution. The existence of phonons suppresses the field phase distribution and fluctuation in the case when the quantum dot molecule is initially in the tunneling-excited state, while it enhances the diffusion and fluctuation of the field phase in the case when the quantum dot molecule is initially in the ground state. The Husimi phase distribution and the Pegg-Barnett phase distribution agree with each other fairly well in our study.