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We theoretically study the cyclotron dynamics of ultra-cold atoms in optical lattices exposed to an artificial magnetic field.The cyclotron orbit and its stability are discussed both analytically and numerically.We find that the cyclotron dynamics of atoms in optical lattices can be manipulated by adjusting the strength of the magnetic field.Atoms can be coherently localized in its initial position,or can be trapped in a priori prescribed orbit doing coherent cyclotron motion,or can be decoherently diffused with time.The stability of the orbit and the coherence of the system present asymmetric characters.Our results provide a direct theoretical evidence for the cyclotron dynamics of neutral atoms in the artificial magnetic field.Furthermore,we theoretically study the reflection and refraction of ultra-cold atoms in optical lattices exposed to a nonuniform artificial magnetic field.The introduction of the nonuniform artificial magnetic field to the optical lattice for suitable designer magnetic potential barrier can lead to a series of intriguing reflection and refraction phenomena of atoms,including reflection,positive refraction,negative refraction and atomic matter wave splitting.Both the occurrence and the distribution of these reflection and refraction scenarios can be coherently controlled by the nonuniform artificial magnetic field.In particular,the regions close to the boundary of reflection demonstrate two more interesting propagation modes,i.e.,a reflected branch of atoms comprising a positive or negative refracted branch of atoms with almost same atom population will be excited simultaneously at the magnetic potential barrier.The results can be a guide for the coherent control of the matter waves in optical lattices and the design of new atom optics devices.