Binding energy of exciton in monolayer semiconductor WS2 with Yukawa-like screening potential

The Yukawa-like screening potential is suggested to describe the effect of environment on the binding energy of an exciton in the monolayer semiconductor WS2. The FK Operator Method combined with the Levi-Civita transformation is used to retrieve energies for the states of  n= 1, 2, 3 which agree with experimental data. Experimental values of the parameters in the screening potential expression are also obtained for further use in the case of presence of external field.