Quantum Interference Effects of Gamma-Radiation in Optically Extended Medium

It is shown that the coherent interaction between gamma quantum and a large nuclear ensemble induces the spatial dependence of refraction index on radio-frequency field phase. It leads to the occurrence of an optically non-homogeneous structure. Both the conditions of electromagnetically induced transparency (EIT) and of maximum absorption of probe gamma field, caused by an exchange with radio-frequency reservoir, were obtained. The evolution of both the EIT regime and the group velocity of slow gamma photons were analyzed. The influence of gamma pulse duration, polarization of radiation and linear dimensions of a medium was explored.