Quantum Gas Jet-based Helium Atom Microscope (qHAM)

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Conventional microscopy tools have a number of limitations: Light microscopy is intrinsically limited to around micron length-scales; electron microscopy often leads to sample damage or charging; and scanning probe methods (such as atomic force microscopy) are limited to small areas on predominantly flat surfaces.These limitations cause significant problems for surface morphological studies: delicate samples such as 2-dimensional organic thin films risk being damaged by energetic electron beams; more complex insulating structures cannot be imaged with high resolution by electron beams as they are accumulating charges; and bio-materials with complex topographies cannot be imaged by conventional scanning probe techniques such as Atomic Force Microscopy (AFM).This project will overcome these limitations by exploiting two quantum phenomena: Wave-Matter duality and matter wave Interference. The de Broglie wavelength ? of a particle is related to its momentum p by ?=h/p, where h is Planck's constant. For a helium atom moving with thermal velocity at room temperature, the average de Broglie wavelength is 0.9 Angstroem. An atom sieve designed on the principle of Fresnel Zone Plates (FZP) achieves a focus at the point where the path difference between molecules travelling via adjacent zones is equal to one wavelength. From this condition, the radius at the focal point can be derived - this extremely small and in the micrometer range, giving access to high resolution imaging.A quantum gas jet-based Helium Atom Microscope (qHAM) will be developed as a compact, low cost and table-top microscope with superior imaging capabilities.