Resumen
The present invention relates to a device for coherently reflecting a beam of atoms or molecules, said device comprising a crystalline substrate with a high-quality surface on which a metal surface structure is deposited such that the specular reflectivity of the beam is about 20 % or higher and a method for producing the same. It further relates to an atom-optical apparatus containing said device and its use in high vacuum or ultra-high vacuum systems, and a method for reflecting a beam of atoms or molecules by using said device.
Reivindicaciones
1. Device for coherently reflecting a beam of atoms or molecules comprising a crystalline substrate with a high-quality surface on which a metal surface structure is deposited such that the specular reflectivity of the beam is about 20 % or higher. 2. Device according to claim 1, wherein the crystalline substrate is a semiconductor. 3. Device according to claim 1 or claim 2, wherein the atoms or molecules are selected from the group consisting of He atoms, Ne atoms, H<2> molecules or O<2> molecules. 4. Device according to any one of the preceding claims, wherein the crystalline substrate is based on silicon or germanium. 5. Device according to any one of the preceding claims, wherein the crystalline substrate is a silicon wafer. 6. Device according to any one of the preceding claims, wherein the metal is selected from the group consisting of lead, tin, silver, gold, copper and aluminium or mixtures thereof. 7. Device according to any one of the preceding claims, wherein the crystalline substrate is a silicon wafer having a Si(111)(7x7)-surface which is atomically flat over lateral scales of the order of 1 micron. 8. Device according to any one of the preceding claims, wherein the substrate with the metal surface structure is selected from the group consisting of (2x1), (2x2), (2x4), c(8x4) and c(4x4) Pb structures on Si(100) and a (√3x√3)Pb/Si(100)R30 structure. 9. Device according to any one of the preceding claims, wherein the metal structure has a height of 2, 3, 4, 5, 6, 7, 8, 9, 20 or more layers. 10. Method for producing a device as defined in any of the preceding claims, said method comprising the following steps: a) providing under high vacuum or ultra-high vacuum conditions a crystalline substrate with a high-quality surface; b) depositing on top of the high-quality surface of the crystalline substrate a metal to form a metal surface structure. 11. Method according to claim 9, further comprising a heating step after step (b) to improve the surface structure and/or to desorb a certain amount of the metal deposited in step (b). 12. Method according to claim 10, wherein subsequently to the heating step further metal is deposited and potentially subjected to a further heating step. 13. Method according to claim 10 or claim 11, wherein the heating step is conducted in the temperature range of 650 to 750 K, in particular at about 700 K. 14. Atom-optical apparatus, containing a device as defined in any of claims 1 to 9 or as prepared according to any of claims 10 to 13. 15. Atom-optical apparatus according to claim 14, wherein the atom-optical apparatus is selected from the group consisting of a microscope, a scanning helium atom microscope (SHeM), a lithography device, a holography device, an interferometer or a beam-cooling device. 16. High vacuum or ultra-high vacuum system comprising a device as defined in any of claims 1 to 9 or as prepared according to any of claims 10 to 13, or an atom-optical apparatus according to claim 14 or 15. 17. Method for focusing a beam of atoms or molecules by using a device as defined in any of claims 1 to 9 or as prepared according to any of claims 10 to 13. 18. Method for operating an atom-optical apparatus as defined in any of claims 14 and 15 using the scattering of atoms or molecules, under high vacuum or ultra-high vacuum conditions, comprising providing a beam of atoms or molecules, reflecting the beam by using a device as defined in any of claims 1 to 9 or as prepared according to any of claims 10 to 13, and detecting the diffraction or transmission intensities of the beam after interaction with a material to be examined. 19. Method according to claim 18, wherein the beam is focused.
