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.

中文翻译：

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应用线性组合运算法研究非对称半指数量子阱中弱耦合电子的相干时间

我们首次使用线性组合算符方法从理论上研究了对称半指数量子阱量子位的相干时间特性。我们使用幺正变换和费米黄金法则推导出量子阱势垒高度和非对称半指数限制势 (ASECP) 范围对振动频率、第一激发态 (FES) 能量、激发能量和相干时间的影响。我们发现振动频率、FES 能量和激发能量是势垒高度的递增函数，但在 ASECP 范围内是递减函数；然而，相干时间具有完全相反的特性。我们的结果可能对固态量子计算的设计和实现有用。