Articles
Ultrafast Laser Micromachining Creates Surface Modifications to Assist R&D Developments
Ultrafast laser micromachining of surface modifications produce geometrical structures that conduct very precise functions. As the demand for device miniaturization continues, ultrafast or femtosecond laser micromachining produce surface reliefs on a micrometric or even nanometric scale and with high aspect ratios. Application examples Surface chevrons for enzyme reactions in point-of-care tests Lab-on-Chip microfluidic channels and microholes Security identification markings Creating diffractive, absorbent, adhesive surfaces 3D structuring of dielectrics, silicon, polymers, thin-films, integrated optics
Using Lasers to Produce Faster Electronics and Better Solar Cells
Recently, the concept of integrating photonics and electronics, with the goal of producing faster electronics and more effective solar cells, has been attracting a significant amount of interest. To properly understand this idea, the small-scale electronic and photovoltaic processes must be investigated on the atomic or molecular level. Prof. Hrvoje Petek and his research group at the University of Pittsburgh are aiming to do just that, operating under the notion that processes cannot be controlled until they are adequately measured. To perform their investigations, the research group used [...]
Using Label-free imaging techniques to further understanding of Multiple Sclerosis
Multiple Sclerosis (MS) is an autoimmune inflammatory disease that affects nearly 2.3 million young adults worldwide. In cases of MS, the immune system promotes an attack on the central nervous system (CNS), often leading to disability and degeneration. The MS lesion is traditionally considered the leading indicator of CNS damage and thus has been studied for decades through various clinical pathological methods. However, it has been found that surrounding regions in the brain, known as 'normal-appearing' white matter (NAWM), also present some abnormalities in MS cases. Label-free imaging [...]
Burning Coal with Femtosecond Laser Pulses
Since before the industrial age, graphite materials have played an essential role in daily life: their properties are seen in everything from burning embers to the first electric bulbs. Even as technologies advance, graphite materials continue to pique interest in the human mind. One example is graphene, a two-dimensional material with remarkable optical and electronic properties, which has sparked a renewed interest in the field of semiconductor research, particularly in studies of solar energy conversion. Prof. Hrvoje Petek and his research group at the University of Pittsburgh are [...]
Progress of Industrial Femtosecond Machining – A Rich 20-year History
Micromachining with femtosecond lasers (also known as ultrafast or ultra-short pulse lasers) is gaining popularity due to several advantageous properties, including the nearly athermal, or "cold," ablation process. For industries demanding smaller and more precise parts, this technology offers several benefits, including higher yields, tighter tolerances, little to no collateral damage, and no post processing. While femtosecond lasers have begun gaining significant attention in recent years, they were originally showcased 20 years ago at the Laser World of Photonics in Munich, Germany by Clark-MXR, a company founded in [...]
Catching Molecules in the Act
Chemical reactions are characterized by the motion of atoms; transformation of chemical compounds, reactants, and raw materials is therefore governed by molecular vibrations. While the motion of the atoms is easily seen at the beginning and end of a chemical reaction, the molecular changes occur too rapidly in the middle of the process, making them impossible for humans to observe. With novel techniques that employ the use of ultrafast lasers, however, we can essentially freeze the chemical reaction. This allows us to thoroughly observe the intermediate steps of [...]