Optics Express
High resolution electromagnetically induced transparency spectroscopy of Rydberg ^87Rb atom in a magnetic field
Hong Cheng, H. M. Wang, S. S. Zhang, Peipei Xin, J. Luo, Hongping Liu
Abstract
We have studied the high resolution spectroscopy of Rydberg state 87Rb in a ladder-type electromagnetically induced transparency (EIT) configuration at room temperature. A highly excited Rydberg atom is nearly degenerate for its hyperfine states but this degeneracy will be broken by an applied magnetic field, resulting in a spectral splitting in a coupled basis. In our ladder-type EIT experiment, we observed the high resolution spectral splitting of Rydberg atoms in an external magnetic field with two different optical polarization combinations of σ+ − σ+ and σ+ − σ− for probe and coupling laser beams. A strict theory has been set up to explain the observed spectral line position and intensity accurately considering the Zeeman effects of three EIT-concerned states all in the coupled basis. Specially for the Rydberg state, we can transform its wavefunction back into the decoupled basis for the spectral line assignment.