Nanolithography with ultra-short laser pulses

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Lithography is a key technology enabling progress both in fundamental research and in widespread applications. It is usually discussed in the context of the semiconductor industry and Moore's law: the industry's ability to quadruple the number of transistors on a chip every three years. In an effort to keep up with quickly "shrinking" transistor size, alternative lithographic techniques are actively explored, and among them - atom nanolithography. In contrast to conventional optical lithography, which uses monochromatic beam of light, atom lithography utilizes the beam of atoms which is manipulated by optical fields before being deposited on a solid surface. In both cases the resolution is dictated by the diffraction limit, and therefore by wavelength of the corresponding beam. While optical wavelengths are in the range of a few hundred nanometers, the wavelength of a matter wave of atoms is measured in picometers. It is therefore particularly attractive to use atom optics for pushing the boundaries of nanolithography and reaching much shorter length scales in nanofabrication. Here I propose to establish an innovative program on atom nanofabrication with ultra-short laser pulses. This program will have two main objectives. First, we will develop the technology of controlling atomic and molecular motion with pulsed optical fields. And second, the new technique will be applied to tackle two major shortcomings of atom lithography with continuous-wave laser sources: 1) its limited applicability to only a small selection of atoms, and 2) its inherent restriction to only periodic nanostructures. Based on non-resonant interaction of atoms with high-power femtosecond pulses, such as multiphoton ionization, the proposed method will be extended to even complex molecules. Broad spectral bandwidth of short pulses and their tight localization in space will enable control of molecular distribution beyond currently demonstrated periodic modulation. The new experimental technique will bridge ultrafast optics, atomic physics and nanoscience, stimulating a whole new direction of research, and attracting students to this fascinating interdisciplinary field.