For nanoparticles, controlling strong electromagnetic fields is the key to triggering targeted molecular reaction on their surfaces. Laser light enables to exercise such strong control over electromagnetic fields.
Although in the past, laser-induced formation and disintegration of molecular bonds on surface on nanoparticles have been observed, nanoscopic optical control of surface reactions has not yet been achieved.
A team of physicists at Ludwig- Maximilians Universitat and Max Planck Institute of Quantum Optics in collaboration with Standford University have now closed this gap.
For the first time, physicists determined the position of light-triggered molecular reactions on the surface of solitary silicon dioxide nanoparticles with the help of ultrashort laser pulses.
This results in hustle and bustle on the surface of nanoparticles. Molecules anchor, dissolve, and change their location. All this steers chemical reactions, transforms matter and even leads to new substances.
In fact, electromagnetic fields can help for sway on occurrences of nanocosmos. This has been demonstrated by two physicists at Nanophotonics Group and Ultrafast Electronics.
To demonstrate this, researchers used solid, femtosecond laser pulses to produce localized fields on the surface of solitary nanoparticles.
Meanwhile, employing reaction nanoscopy – a recently developed new technique in the same group, physicists were able to capture the reaction site and origin site of molecular parts on the surface of silica nanoparticles.
Importantly, scientists successfully attained the nanoscopic spatial control attainable at even higher resolution. Scientists did this by superimposing the fields of two laser pulses with different color, polarization, and controlled waveform.
Thereby, they had to set the time difference between the two pulses with an accuracy of attosecond.
In terms of value, an attosecond is thousand times lesser than femtosecond.