Emending thermal dispersion interactions of Li, Na, K, and Rb alkali-metal atoms with graphene in the Dirac model

Using accurate dynamic polarizabilities of the Li, Na, K, and Rb atoms, we scrutinize the thermal Casimir-Polder interactions of these atoms with a single-layered graphene. Considering the modified Lifshitz theory for material interactions, we reanalyze the dispersion coefficient (C-3) values of the above atoms with graphene as functions of separation distance, gap parameter, and temperature, among which some of them were earlier studied by estimating the dynamic polarizabilities of the above atoms using the single oscillator model. All these C-3 coefficients have been evaluated in the framework of the Dirac model. The interactions are described for a wide range of distances and temperatures to demonstrate the changes in behavior with the varying conditions of the system. Also, sensitivities of the interactions with the gap parameters are analyzed explicitly. From these analyses, we find a suitable region where measurements of interaction potentials can be carried out so that a justifiable value for the gap parameter can be surmised.