Category Technology/Electronics

“Device” is a disc 250 nm in diameter that is capable of switching optical pulses at femtosecond rates (femtosecond is a one millionth of one billionth of a second). Credit: Maxim Scherbakov et al

Researchers developed an ultrafast all-optical switch based on nonlinear dielectric silicon nanostructures. The operation of the switching is based on the interaction between 2 femtosecond pulses; at the same time, the undesirable free-carrier effects are suppressed. Ultrafast optical switching will permit to create data transmission and processing devices which will handle speeds high enough to download 1000s of HD-movies/sec.

Photons address the data transmission problem better than electrons...

Depiction of the vOICe encoding scheme. A camera mounted on glasses records video that is converted to sound by a computer and transmitted to headphones in real time. Credit: Shimojo Lab/Caltech

Caltech researchers have now discovered that intrinsic neural connections- crossmodal mappings -can be used by assistive devices to help the blind detect their environment without requiring intense concentration or hundreds of hours of training. This new multisensory perspective on such aids (called sensory substitution devices) could make tasks that were previously attention-consuming much easier, allowing nonsighted people to acquire a new sensory functionality similar to vision.

“.. 99% of our daily life depends on multisensory- also called multimodal processing...

The researchers, led by University of Cambridge, used ultrafast laser pulses to observe how a photon, can be converted into 2 energetically excited particles, known as spin-triplet excitons, through a process called singlet fission. If the process of singlet fission can be controlled, it could enable solar cells to double the amount of electrical current that can be extracted.

In conventional semiconductors such as silicon, when 1 photon is absorbed it leads to the formation of 1 free electron that can be harvested as electrical current. However certain materials undergo singlet fission instead, where the absorption of a photon leads to the formation of 2 spin-triplet excitons...

a) This image shows loading clay nanotubes with drug from saturation solution. b,c) Mixing with drug solution, pumping out air, and pulling in drug molecules, washing, and loaded tubes. Credit: Yuri Lvov, Wencai Wang, Liqun Zhang, Rawil Fakhrullin

Halloysite is a natural biocompatible nanomaterial available in thousands of tons at low price, which makes it a good candidate for nanoarchitectural composites. In vitro and in vivo studies on biological cells and worms indicate the safety of halloysite, and furthermore, it can store and release molecules in a controllable manner, making these tiny containers attractive for applications in drug delivery, antimicrobial materials, self-healing polymeric composites, and regenerative medicine.

In chemical composition they are similar to kaolin and c...