A nanosized laser beam for the fabrication of nanopores for DNA sequencing

Y. Wang
Yancheng Teachers University,
China

Keywords: multilayer planar films, laser beam without diffraction spreading, femtosecond nano-machining

Summary:

We use two different materials before the output window of a laser: one is a “dark” planar metal-dielectric film that absorbs light thoroughly into surface plasmon-polaritons (SPPs), and another is a “transparent” dielectric material that reduces SPPs to free-space optical waves. Therefore this technology builds a laser beam without diffraction spreading, and it is transformational to generate a strong beam spot of a few nanometers. Current the most promising DNA sequencing device, the solid-state nanopores with nano-meter-thin constrictions, is produced by an energy-dissipative “cold ion beam sculpting” procedure. It is ideal to fabricate such nanopores with a femtosecond laser directly. However, existing ultrafast laser micromachining is based on the extraordinary peak power of a tightly focused pulsed laser, whose size is fundamentally limited by optical diffraction, to induce desired patterns. Therefore existing laser technology cannot reach an intense beam spot of a few nanometers. Our nanopore DNA sequencing device will offer fast cost-effective solution for DNA sequence and will make routinely prescription of DNA sequencing possible for the detection of cancer. Our novel technology will also generate a variety of photonic devices and other medical applications from eye surgery to dentistry.