Laser ablation of Nickel, Copper, Molybdenum, Indium, Tungsten and Gold by short ultraviolet laser pulses (0.5 ps, 248 nm) in vacuum is reported for the first time. For Nickel and Indium, ablation is also studied in air to demonstrate the influence of the ambient atmosphere. Metal ablation in air is significantly less efficient than in vacuum due to redeposition of ablated material. The ablation rates in vacuum are discussed using a thermal model, which also allows to estimate ablation rates for other metals from basic optical and thermal properties. A comparison of the morphology of ablation sites after nanosecond and sub-picosecond ablation shows unequivocally the advantages of short-pulse laser ablation for high-precision patterning of thermally good conducting materials in micron-scale dimensions.

Experiments on the ablation of undoped polytetrafluoroethylene (Teflon) with 300 fs UV excimer laser pulses at 248 nm are reported for the first time. In contrast to standard excimer laser pulses, these ultrashort pulses ablate Teflon with good edge quality and no signs of thermal damage for fluences down to 0.5 J/cm2 with removal rates on the order of 1 μm per pulse.

Three-dimensional periodic microstructures of aluminum oxide, which are important for creating photonic band-gap structures (PBGs), were fabricated by laser rapid prototyping by means of laser-induced direct-write deposition from the gas phase. The structures consisted of layers of parallel rods forming a face-centered tetragonal lattice with lattice constants of 66 and 133 micrometers. These structures showed transmission minima centered around 4 terahertz (75 micrometers) and 2 terahertz (150 micrometers), respectively. PBGs will allow precise control of the optical properties of materials, including lasers without threshold.

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A method is described that demonstrates a new technique for rapid and high‐throughput single molecule sequencing. This sequencing technique is based on the successive enzymatic degradation of fluorescently labeled single DNA molecules, and the detection and identification of the released monomer molecules according to their sequential order in a microstructured channel. The detection technique is evolved from confocal fluorescence microscopy, with two different laser sources to excite the individual mononucleotides that are either labeled with tetramethylrhodamine (TMR) or Cyanine5 (Cy5). The handling of DNA which is immobilized on carrier beads, and the detection of the cleaved monomers is performed in optically transparent and biochemically inert microstructures (glass or PMMA) with detection channels of 7 μ × 10 μm. The projected rate of sequencing is ≈100 bases min−1, dependent solely on the rate of the enzymatic DNA cleavage.