Laser-focused nanofabrication: Beating of two atomic resonances

We deposit a laser-collimated chromium beam onto a substrate through a laser standing-wave (SW) tuned above the atomic resonance at either of the two 52Cr transitions S3 → 7P o 3 at 427.600 nm or S3 → 7P o 4 at 425.553 nm. In both these cases the resulting pattern on the surface consists of nanolines with a period of that of the SW. We extend the range of periods accessible to laser-focused atom deposition by superimposing the structures grown at both these resonances. The resulting beating pattern exhibits a period of 44.46 ± 0.04 μm as determined with a polarizing optical microscope. This structure provides a link between nanoscopic and macroscopic worlds and could potentially become a calibration standard for length metrology. PACS number(s): 42.50.Vk, 03.75.Be, 81.16.-c, 06.20.-f Typeset using REVTEX