New Optical Tweezers Put on the Pressure to Change Color
upstart writes:
New optical tweezers put on the pressure to change color:
Scientists demonstrate an optical trapping technique using nanotextured black silicon that can efficiently trap polymer chains. By adjusting the laser intensity, these 'optical tweezers' can control the florescence color emitted through a local concentration of a perylene-modified polymer solution. From a low intensity blue to high intensity orange, this reversible and fully remote technology can almost reach the entire RGB spectrum.
One big stumbling block in the field of photonics is that of color control. Until now, to control color, i.e. the wavelength of light emission, researchers would have to alter the chemical structure of the emitter or the concentration of the solvent -- all of which require direct contact, greatly limiting their application.
"Such conditions make it impossible to change color quickly, use it as a light source in microscopic spaces like a cell, or in closed systems where exchange is not an option," says Yasuyuki Tsuboi and professor of the Department of Chemistry, Osaka City University. With "optical tweezers," a technology he developed in previous research, Prof. Tsuboi led a team of researchers to show it possible to control the luminescence color remotely, using only the effect of light pressure.
[...] "We observed the color of the fluorescence emitted by the polymer aggregate change in response to this," explains Prof, Tsuboi, "with low intensities producing blue, and then changing to green, yellow, green yellow, to orange as the intensity increases." As the laser intensity is what is being controlled, the color change is fully reversible and able to be done remotely.
Journal Reference:
Ryota Takao, Kenta Ushiro, Hazuki Kusano,et al. Fluorescence Colour Control in PeryleneLabeled Polymer Chains Trapped by Nanotextured Silicon. Angewandte Chemie International Edition, 2022; 61 (11) (DOI: 10.1002/anie.202117227)
Read more of this story at SoylentNews.