Temperature Dependence of Nonradiative Transitions of an Excited Optical Ion in Solids

摘要

We have investigated the temperature dependence of nonradiative transitions of an optical ion in a solid from the excited electronic state to the ground electronic state within the framework of proper adiabatic approximation for a single configuration coordinate,q. The Hamiltonian based on the nonadiabaticity operator has been used to calculate the temperature dependence of nonradiative transition rates. This perturbing Hamiltonian, H-na = -h(2)(partial derivative partial derivative q)(e)(partial derivative/partial derivative q)(nu) - h(2)/2(partial derivative(2)/partial derivative q(2))(e) (I)(nu) consists of two terms. In the literature, the first term is usually used to explain nonradiative transitions of an optical ion in a solid. We have shown that the first term alone leads to a zero of the nonradiative transition rates when s = z for low temperature, where s represents the Huang-Rhys parameter and z relates to the energy gap between the excited state and ground state in terms of vibrational quantum of energy, h omega. This zero cannot be removed unless the second term is included for calculating the transition rates. We have defined three auxiliary functions, U-1, U-2 and U-3 to describe the temperature dependence of the nonradiative transition rates in a physically meaningful way. (C) 2022 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.