Tag: organic

Boffins create disposable lasers

White laserFrench Researchers have worked out a way of creating cheap lasers with an inkjet printer which can be thrown away after it’s been used once.

Sébastien Sanaur, an associate professor in the Center of Microelectronics in Provence at the Ecole Nationale Supérieure des Mines de Saint-Étienne in France said that the low cost and easiness of laser chip fabrication are the most significant aspects of his teams results.

Organic lasers are not as common as inorganic lasers, like those found in laser pointers, DVD players, and optical mice, but they offer benefits such as high-yield photonic conversion, easy fabrication, low-cost and a wide range of wavelengths.

One obstacle that has held back organic lasers they degrade quickly – but that hurdle might be less daunting if the lasers are so cheap they could be thrown out when they fail.

The researchers used two different types of dyes to produce laser emission ranging from yellow to deep red. The ink was printed in small square shapes onto a quartz slide.

The dyed ink acted as the core of the laser, called a gain medium.  A gain medium amplifies light and produces the characteristically narrow, single-colour laser beam.

A laser also requires mirrors to reflect light back and forth through the gain medium and an energy source, called a pump, to keep the light amplification going. The disposable part of the new laser is the printed gain medium, which the researchers call the ‘lasing capsule.’

The researches could build one for only a few cents.  The lasing capsule could be easily swapped out when it deteriorates.

Researchers come close to organic memory

A team of researchers have had a breakthough in creating artificial short-term memories in brain tissue.

Ben Strowbridge and Robert Hyde, from the Case Western Reserve University School of Medicine, have discovered how to store diverse forms of artificial short-term memories in isolated brain tissue.

This will pave the way for computers which have bio-mechanical memories and servers run by rat brains.

In their book, with the catchy title “Mnemonic Representations of Transient Stimuli and Temporal Sequences in Rodent Hippocampus In Vitro,” Strowbridge said that what they had found was a way to store information over seconds about both temporal sequences and stimulus patterns directly in the brain.

This paves the way for future research to identify the specific brain circuits that allow us to form short-term memories.

Organic memories are often grouped into two categories: declarative memory, the short and long-term storage of facts like names, places and events; and implicit memory, the type of memory used to learn a skill like playing the piano.

Using isolated pieces of rat brain tissue, the researchers demonstrated that they could form a memory of which one of four input pathways was activated.

Neural circuits stored in the hippocampus maintained the memory of stimulated input for more than 10 seconds. The information about which pathway was stimulated was evident by the changes in the ongoing activity of brain cells.

Hyde said that that it was possible to generate memories for specific contexts.

Work on memory is important for the study of neurodegenerative diseases, such as Alzheimer’s or Parkinson’s disease. But they are also being looked at for bio hardware computing where a chip is replaced by a hyper-efficient collection of rat brains. While these might be more difficult to look after and have the tendency to send your server running up drain pipes they will use a lot less power and be a lot faster than silicon.