Goos-H\"{a}nchen-Like Shifts in Atom Optics

We consider the propagation of a matter wavepacket of two-level atoms through a square potential created by a super-Gaussian laser beam. We explore the matter wave analog of Goos-H\"{a}nchen shift within the framework of atom optics where the roles of atom and light is exchanged with respect to conventional optics. Using a vector theory, where atoms are treated as particles possessing two internal spin components, we show that not only large negative but also large positive Goos-H\"{a}nchen shifts can occur in the reflected atomic beam.