New Signal Amplification, Cycling Excitation Process (CEP), Opens Up New Generation of Electronic Systems

Researchers from the University of California, San Diego has discovered a new signal amplification process called CEP or Cycling Excitation Process.

CEP can amplify photocurrents at a much lower voltage and noise than current existing methods.

Current semiconductor devices use photodetectors and low-noise electronic amplifiers to convert optical signals into electronic signals with amplification to enable information detection and processing. The UC San Diego team found a more efficient method by modifying the p/n junction, a boundary or interface between two types of semiconductor material inside a single crystal of semiconductor.

CEP can be used in devices and semiconductors which opens up a myriad of possibilities in the semiconductor industry; communication and imaging devices with superior sensitivity can be produced at a low cost.

New types of transistors and circuits can also be produced that furthers the scope of applications past optical detection.

Magnetic Mystery Behind Lanthanum Aluminate and Strontium Titanate Combine Computer Processors with Memory Chips

Scientists have theorized how two non-conductive and non-magnetic materials, Lanthanum Aluminate and Strontium Titanate, become conductive and magnetic when combined together. This phenomenon can lead to the development of computer memory with data processing capabilities.

Scientist believe that because of a magnetic phenomenon called "local moments", lanthanum aluminate and strontium titanate, become conductive and magnetic when placed together. With these two properties, these two semiconductors have the ability to process binary data (like a computer processor) and also have the ability to store them (like a memory chip) in one device; a computer processor that can store data.

A semiconductor is a material that has conductive properties midway between a conductor like metal and a non-conductor such as glass. Because of this, depending on the flow of electrons in the semiconductor, it can be either on (1) where electrons can flow freely or off (0) when electrons cannot pass through. Data that is streamed through these semiconductors can be permanently stored on magnetic devices.

Conductive Liquid Cement Developed From Mayenite and CO2 Laser Beam Heating

Researchers from the Japan Synchrotron Radiation Research Institute/SPring-8 in collaboration with scientists from Finland, Germany, and the United States have created liquid cement that has the conductive properties of metal. SPring-8 is a synchrotron radiation facility located in Japan and is operated by the Japan Synchrotron Radiation Research Institute.

Cement is a substance that sets and hardens independently. It helps bind other materials together such as it does with concrete when it is combined with limestone, granite, or sand.

The recent discovery means that this type of conductive liquid cement can lead to semi-conductors that have low energy loss and is easy to mold into different shapes and configurations. Possible applications in electronics for this material can be developed in LCD monitors, protective coatings, and even in computer chips.

MIT News: Energy Efficient And Precision Controlled Quantum Dots Developed

MIT researchers have developed a new production method in creating quantum dots that can control its size and shape, and also vastly improves the quantum dot's emission efficiency. This allows the development of energy efficient and precise devices such as computer screens and biomedical kits and applications.

In simple terms, quantum dots are nano-scale semiconductors that converts light into energy. These are parts of matter whose excitons (photons absorbed by a semiconductor) are bound in all three spatial dimensions. They are so small that quantum dots can be applied to most substrates or surfaces by spraying it on to form a layer of nano-film semiconductors.

Quantum dots are just a few atoms thick making it viable for use in nano-sized or micro-sized devices. Currently, some transistors, LEDs (Light emitting diodes), solar panels, and diode lasers utilize this technology. Some are even looking at quantum dots for use in quantum computers.

Spintronic 3D Microchip Developed

A new type of microchip based on spintronic technology was created that not only moves information from left to right and back to front, but up and down as well.

In electronics, semiconductors utilize the electrical charge carried by the electron. It carries either a positive charge or negative charge. Information is based on the charge of these electrons.

Aside from the electrical charge, electrons also has another property; its spin. The spin of an electron makes it behave like a bar magnet. It either points up or down. Spintronic technology takes advantage of this property to add one more component in storing information in an electron. Aside from the charge which could either be positive or negative, it can also carry information based on the spin which is either up or down.

Spintronic devices act according to the following scheme:

1. Information is stored (written) into spins as a particular spin orientation (up or down).
2. The spin, being attached to mobile electrons, carry the information along a wire.
3. The information is read at a terminal.

The spin orientation lasts longer than electron momentum (nanoseconds -10x^-9 compared to femtoseconds -10x^-15). This makes it optimal for applications such as memory storage and magnetic sensors applications.

Because of the efficiency in storing and transmitting information, spintronic based devices are smaller, cheaper, stable and more accurate than existing conventional devices. At the moment, some hard drives use this technology in data storage.

Organic Ferroelectric Molecule Developed As An Alternative To Silicon For Semiconductors

Electrical response overlaid on the newly characterized organic molecular crystal.
Credit: Jiangyu Li, University of Washington

Diisopropylammonium bromide is a new organic molecule synthesized from bromine, carbon, hydrogen and nitrogen that may be an alternative to silicon for use in semiconductors and other memory, sensing and low-cost energy storage applications.

Organic molecules are molecules that contain carbon. Carbon is a versatile atom and can attach easily to other atoms (forming 4 covalent bonds). The science of designing, synthesizing, characterizing, and developing applications for molecules that contain carbon is called organic chemistry.

Organic molecules are often associated with living things but for organic compounds this is not necessarily the case. The term comes from the old belief that certain compounds and molecules require a "life-force" of a living thing to be generated. The belief has been discredited but the term still remains.

Organic chemistry applications range from the medical to the industrial. One role of organic chemists is to synthesize and develop new molecules that will address a problem or enhance a product.

Synthetic organic compounds usually carry properties that enhance a process, mitigate or address a design/process flaw, or solve a problem. Most of these applications can be seen in pharmaceutical and consumer products.

World Smallest Semiconductor Laser - Breakthrough in Photonic Technology

Semiconductor lasers are eyed to be the next generation in laser technology. These lasters are compact, can be mass produced, easily integrated into applications, their properties are being improved constantly, they are becoming more and more powerful and efficient and they have found a widespread use as pumps for solid–state lasers.

The active medium of the laser is a semiconductor. This is similar to the ones found in an LED. The most common of this is formed from a p-n junction and powered by injected electric current. The former devices are sometimes referred to as injection laser diodes to distinguish them from optically pumped laser diodes.

The majority of the materials used by the semiconductor are based on a combination of elements in the third group of the Periodic Table (Aluminum (Al), Gallium (Ga), Indium (In)) and the fifth group (Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb)). This group of elements are referred to as the III-V compounds. Examples include GaAs, AlGaAs, InGaAs and InGaAsP alloys. The cw laser emission wavelengths are normally within 630~1600 nm, but recently InGaN semiconductor lasers were found to generate cw 410 nm blue light at room temperature. The semiconductor lasers that can generate blue-green light uses materials which are the combination of elements of the second group (Cadmium (Cd) and Zinc (Zn)) and the sixth group (Sulfur (S), Selenium (SE)).

This is an illustration of the nanoscale semiconductor structure used for demonstrating the ultra-low-threshold nanolaser. A single nanorod is placed on a thin silver film (28 nm thick). The resonant electromagnetic field is concentrated at the 5-nm-thick silicon dioxide gap layer sandwiched by the semiconductor nanorod and the atomically smooth silver film.
Credit: (c)Science

World's smallest semiconductor laser created by University of Texas scientists

Physicists at The University of Texas at Austin, in collaboration with colleagues in Taiwan, have developed the world's smallest semiconductor laser, a breakthrough for emerging photonic technology with applications from computing to medicine.

The scientists report their efforts in this week's Science.

Miniaturization of semiconductor lasers is key for the development of faster, smaller and lower energy photon-based technologies, such as ultrafast computer chips; highly sensitive biosensors for detecting, treating and studying disease; and next-generation communication technologies.

Such photonic devices could use nanolasers to generate optical signals and transmit information, and have the potential to replace electronic circuits. But the size and performance of photonic devices have been restricted by what's known as the three-dimensional optical diffraction limit.

Nanotechnology And Vacuum Tube Technology For Faster And More Efficient Electronics

A vacuum tube is simply a sealed glass tube or container. The inside of the tube is a space that is empty of any matter or gas; a vacuum. The vacuum tube is a device that controls the current through the vacuum. Vacuum tubes are used for rectification, amplification, switching, or creation of electrical signals.

Thomas Edison discovered this when experimenting with light bulbs. He discovered that when an electric contacts are introduced to both ends, the current jumps from the hot filament of the bulb to a metal plate at the bottom. This is called the Edison Effect.

The Edison Effect or Thermal Electron Emission basically says that electric current can travel through a gas or a vacuum without the need of an electric wire to move through.

The vacuum tube found its use in 1904 when John A. Fleming invented the Diode. A diode is the most simple vacuum tube. It is basically a light bulb with an electrode inside it. The diode works when the bulb's filament is heated white hot and electrons are boiled off its surface and into the vacuum inside the bulb. If the extra electrode is made more positive than the hot filament, a direct current flows through the vacuum to the anode.

Diode

The diode acted like a valve (and it was known as such) because the current in the tube travels exclusively in one direction. This turned out critical for radio sets then since it needed to turn alternating current into direct current, which the diode does.

Lee De Forest followed with his invention of the Audion. This type of vacuum tube performs like a diode but additionally also increases the current along the way. This is done by placing a metal grid in the middle of the vacuum and using a small input current to change the voltage on the grid. An audion can control the flow of the second more powerful current through the tube. The strength of the two currents need not to be related; a weak current can be applied to the tube's grid while a much stronger one can come out the main electrodes of the tube.

Triode

The audion soon led to the Triode. A triode is an three electrode version of the Audion. The triode is basically the first electronic amplifier, It served as an electronic amplifier in radio communications. This revolutionized the production of radio transmitters and receivers. It also led the great improvements to the telephone system in the US.

The invention of the triode ushered in the Electronic Revolution of the 20th century.

Smaller, cheaper, efficient and reliable solid state semiconductor devices such as transistors and solid state diodes have replaced vacuum tubes in modern devices. But some applications still need the use of vacuum tubes such as High Power Radio Frequency Transmitters and Microwave Ovens.

In the music industry, professional musicians still prefer vacuum tube based sound amplifiers because of the quality of sound it produces.

Pitt researchers propose new spin on old method to develop more efficient electronics

With the advent of semiconductor transistors—invented in 1947 as a replacement for bulky and inefficient vacuum tubes—has come the consistent demand for faster, more energy-efficient technologies. To fill this need, researchers at the University of Pittsburgh are proposing a new spin on an old method: a switch from the use of silicon electronics back to vacuums as a medium for electron transport—exhibiting a significant paradigm shift in electronics. Their findings were published online in Nature Nanotechnology July 1.

For the past 40 years, the number of transistors placed on integrated circuit boards in devices like computers and smartphones has doubled every two years, producing faster and more efficient machines. This doubling effect, commonly known as "Moore's Law," occurred by scientists' ability to continually shrink the transistor size, thus producing computer chips with all-around better performance. However, as transistor sizes have approached lower nanometer scales, it's become increasingly difficult and expensive to extend Moore's Law further.