Ultra-fast flash light revealing mystery of atoms, into the world of attoseconds (10-18 second) Beyond the femtosecond (10-15 second) barrierFerroelectric RAM (FeRAM) is a type of non-volatile computer memory, similar to dynamic random access memory (DRAM) which can be found in majority of our computers. FeRAM uses a ferroelectric layer to achieve non-volatility and offers a number of advantages from lower power usage to faster writing speeds.Ferroelectrics such as PbTiO3 have usually two stable oppositely-polarized states without external electric fields, and the negatively-polarized state ca..
Ajoint research between POSTECH (Pohang University of Science and Technology) and Max Planck Institute of Microstructure Physics, Halle, has produced an advanced technology applicable to the development of the permanent memory, FeRAM, which can save 176 billion bits per square inch (published in Nature Nanotechnology, vol. 3, page 402). FeRAM has attracted many researchers’ interest because of its excellent characters such as nonvolatility, fast read and write, and high reliability. However, limitation in realizing large scale integration of ferroelectrics on a single chip has hindered t..
The invention of the scanning tunnel microscope (STM) opened the door to nanoworld, enabling humankind to actually touch and feel the individual atoms at the surface of a material. It has inspired a series of inventions such as the atomic force microscope (AFM), the lateral force microscope (LFM), the magnetic force microscope (MFM), etc. Recently, the scanning probe microscope (SPM), which encompasses all these inventions, has evolved into the millipede technology which has a potential to make competing data storage technologies obsolete. A common denominator of these exciting developments is..
It is well known that plants can fix carbon dioxide (CO2) into sugar. In plant cells, the chloroplast is responsible for fixing carbon dioxide into sugar. Thus chloroplasts as the factory for sugar production play essential roles not only for plants themselves but also for most of living organisms on Earth. However, chloroplasts are not just carbon dioxide fixing factory but also responsible for producing a large number of chemical compounds that are essential for plant growth and development. Interestingly, chloroplasts in plant cells are thought to be originated from ancestral cyanobacterium..
Many clinically important drugs are natural products produced by bacteria and fungi. In particular, polyketide antibiotics have been found to be an extremely rich source of biologically active compounds with a broad range of pharmaceutical activities. Aromatic nitro groups are relatively rare functional groups in natural products including polyketide antibiotics but are found in diverse types of important antibiotics, such as chloramphenicol, pyrrolnitrin, aureothin, azomycin, and rufomycin. Surprisingly, the biosynthesis of aromatic nitro groups is poorly understood. To date, only two enzymes..
Nowadays the term of ‘nano’, which means 10-9 as the SI prefix, is commonly mentioned in the media. Usually, a human hair is taken as a means for lifelike recognition of 1 nanometer. One nanometer is 1/100,000 of a hair, which is too small to observe through optical microscope. When we consider that 1 nm is 3 or 4 atomic scale at the most, similar to DNA with the size of 2 nm, its very small size is true to nature for us. Hence, to control an individual atom and to reveal the mystery of the DNA of human body, ‘nanotechnology’ has been attracting great attention as one o..
As technology continues to get smaller, and as memory needs become more demanding, the microelectronics industry requires devices that are more cost-efficient and lightweight. And, while organic memory materials have shown some promise on improvement in performance and reductions in cost, they still lack some of the essential qualities, such as durable performance even in a harsh condition, needed for application in a wide variety of fields. So-called Non-Volatile Memories (NVM) from thermally and dimensionally stable polymer materials could provide a solution.The devices, developed by Profess..
Improvements in performance and reductions in cost of silicon-based nonvolatile memories, such as flash random access memory (flash-RAM), have rendered floppy discs and many other forms of portable storage obsolete. But for many uses that require data to be written only once, such as archiving and security applications, their cost effectiveness is limited. So-called write-onceread- many (WORM) memories made from low-cost polymer materials could provide a solution. The devices, developed by Professors Moonhor Ree, Ohyun Kim, Su-Moon Park and their research teams, are based on hyperbranched copp..
Climate change caused by increasing atmospheric CO2 is a major environmental problem of the 21st century. There has been much discussion about how to reduce CO2 output and prevent global warming. In this respect, plants are an important part of the overall picture as they are primary CO2 consumers and are directly challenged by increasing CO2 levels. Moreover, plants vary in their responses to elevated CO2. Plants that adapt better to this change are expected to out-compete their neighbors, which would cause instability in present ecosystems and unpredictable changes in weather and climate.In ..
Lord Rayleigh wrote about the two-dimensional whispering gallery mode (WGM) in 1910 after a visit to the dome of St. Paul’s cathedral in London. The whispering cave mode (WCM) is a threedimensional (3D) effect?a toroid with circular helix symmetry?which recent studies have shown can be used to create photonic-quantum-ring (PQR) lasers that emit in the blue-violet part of the spectrum. A research team at Pohang University of Science and Technology (POSTECH, Pohang, Korea) first created 3D WCM lasers that emit in the infrared and red part of the spectrum. To achieve this, professor O&rsquo..