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“Meta-optics” for Matter Waves

With the fast development of matter-wave optics, many of the functions previously operated in light optics have been realised: atom diffraction, mirrors, beam splitters, atom holography, quantum reflection, etc. Similarities and differences originate in the properties of the associated particle: non-zero atom mass, vacuum dispersion for the “de Broglie” waves, influence of the internal atomic degrees of freedom… Along this viewpoint, novel areas in the field of atom optics are presently explored. For instance, it includes the devising of non-diffracting atom nano-beams thanks to a specially designed transverse Stern-Gerlach interferometer [1]. The non-diffracting character is linked to the special shape of the resulting transverse profile which is of the Lorentz type, recalling Bessel beams in light optics [2].