The Effect of Coulomb Impurity Potential on the Coherence Time of RbCl Quantum Pseudodot Qubit

We have considered the pseudoharmonic potential (PHP) for a RbCl quantum pseudodot (QPD) qubit with a hydrogen-like impurity at the center. By employing the Pekar variational method and the Fermi Golden Rule, we study the properties of the coherence time of an electron strongly interacting with longitudinal optical phonon in a RbCl QPD qubit. The coherence time changing with the Coulombic impurity potential strength, the two-dimensional chemical potential of the electron gas, the PHP zero point and the polaron radius is theoretically investigated. The obtained results indicate that ① the coherence time of RbCl QPD qubit decreases with increasing Coulombic impurity potential strength, ② the coherence time is a decaying function of the two-dimensional chemical potential of the electron gas and the PHP zero point, ③ the smaller the polaron radius is, the smaller the coherence time is.