Stern-Gerlach deflection of optical Thirring solitons in a coherent atomic system

We propose a scheme to realize an optical Thirring model and create temporal optical Thirring solitons in a tripod-type atomic gas via double electromagnetically induced transparency (EIT). We show that giant enhancement of the cross-phase modulation for the two polarization components of the probe pulse can be obtained under the condition of the double EIT, and hence the optical Thirring model can be realized. We also show that the system supports stable temporal optical Thirring solitons, which have ultralow generation power and ultraslow propagation velocity. In particular, these temporal optical Thirring solitons may experience a significant Stern-Gerlach deflection when a gradient magnetic field is applied to the system. The results reported here are useful not only for extending the research realm of nonlinear magneto-optics but also for the application in precision measurements, such as the detection of microgradient magnetic fields.