Silicon has been the mainstay of chips because silicon possesses a “Goldilocks” band gap of 1.1 electron Volts (eV), which makes it possible to operate integrated circuits at a low voltage, leading to reduced leakage of current. Another key feature of silicon is that it can be used to make a convenient “native” insulator, in the form of silicon oxide. Silicon oxide managed to serve as an insulator for silicon circuits for many generations of chips, isolating components and reducing gate leakage currents, until high-K dielectrics took over the job a decade ago.
Now researchers at Stanford University and SLAC National Accelerator Laboratory have found that some of the most sought after high-K materials—namely hafnium selenide (HfSe2) and zirconium selenide (ZrSe2)—possess the same perfect band gap seen in silicon when they are thinned down to two-dimensional (2D) materials. As a result, the Stanford researchers have discovered a 2D material version of the handy silicon/silicon dioxide combination that enabled generations of chip designs. But in this case the combination can be shrunk down ten times smaller.
As we start looking towards more comprehensive exploration of the Moon and of Mars, the assumption is that we’re working on sending humans to the surface of those worlds. It’s going to be exponentially more difficult and dangerous than sending robots, but that’s what exploration is all about, right?
There’s an article in the current issue of Science Robotics that discusses an alternative approach—a kind of compromise between sending only humans or only robots. The idea is using robotic telepresence for planetary exploration. From orbit, the authors argue, a small team of humans would remote operate rovers and other robotic systems and as a result they could do more exploration while keeping the overall mission safer and cheaper.
A wireless industry consortium is developing a new technology called MulteFire that it says delivers the high performance of 4G LTE cellular networks while being as easy to deploy as Wi-Fi routers.Rather than relying on the licensed spectrum purchased for today’s LTE service, MulteFire operates entirely in the unlicensed 5 gigahertz band. And to set it up, users would simply need to install MulteFire access points, similar to Wi-Fi access points, at any facility served by optical fiber or wireless backhaul. Once installed, MulteFire would provide greater capacity, range, and coverage than Wi-Fi, because it’s based on advanced LTE standards. But by operating in unlicensed spectrum, MulteFire could conserve resources for companies struggling to meet customers’ data demands.
5G technologies are early in their development, and the business cases for them are a bit fuzzy, but wireless researchers and executives still had plenty to celebrate this week at the annual Brooklyn 5G Summit. They’ve made steady progress on defining future 5G networks, and have sped up the schedule for the first phase of standards-based 5G deployments.
A world of millimeter-wave networks, laid out by computer, crisscrossing cities and into the stratosphere, where cell phone towers can be easily replaced by tethered autonomous copters—that’s the telecommunications infrastructure of the future. So says Facebook’s Yael Maguire, head of the company’s Connectivity Lab.
An international team of researchers has developed a low-power gas sensor chip that can operate at room temperature, making possible the development of personal air-quality monitoring devices that we could carry around with us. In research described in the journal Science Advances, the team of researchers fabricated a chemical-sensitive field-effect transistor (CS-FET) platform based on 3.5-nanometer-thin silicon channel transistors. The platform, which is highly sensitive but consumes a small amount of power, can detect a wide range of different gases.
Researchers at IBM Research Alamaden have developed a new approach to measuring the magnetic field of individual atoms that for the first time gives scientists the ability to put the sensor exactly next to the atom they want to measure, providing them with a strong and direct signal of the magnetic field. The energy resolution that the new technology provides is more than 1000 times higher than other microscopic techniques, according to its inventors.
IEEE’s 5G wireless initiative has the goal of serving many more users with much higher transmission speeds. But with the existing cellular bands tightly packed, where does all the required additional network capacity come from? In contrast with the traditional radio-spectrum management view of scarce capacity, where a finite amount of spectrum must be divided up among users, communication theorists see wireless capacity as virtually unlimited. Capacity can be increased indefinitely by going to ever smaller cells and higher frequencies that offer more bandwidth, while greater efficiency can be achieved with advanced signal processing and new spectrum-sharing policies. Among all these approaches, the greatest immediate impact would be achieved by moving to the higher frequencies in the millimeter range—the region of 30 to 300 gigahertz, where bandwidth is available and plentiful.
The Hubble Space Telescope might not make it to 2030. Currently operating 12 years beyond its original 15-year lifespan, Hubble's science operations are slated to end in 2021. A proposed servicing mission could keep the beloved space telescope running even longer, but eventually, the era of Hubble will come to an end. Fortunately, a number of new telescopes, both in space and on the ground, are currently being developed to probe the cosmos like never before. Here is a look the five scopes we are most excited about.
To make it easier for factories to integrate new wireless technologies, U.S. federal government employees took it upon themselves to measure the performance of radiofrequency signals in three factory settings: an auto transmission assembly facility, a steam generation plant, and a small machine shop. They recently published their results as part of an ongoing $5.75 million project aimed at improving industrial wireless led by the National Institute of Standards and Technology (NIST).
In the face of concerted industry opposition, the Federal Communications Commission (FCC) has given the go-ahead for a controversial smartphone accessory that uses microwaves to send text messages and email via geostationary satellites. Startup Higher Ground now has permission to deploy up to 50,000 SatPaq devices across the United States, promising isolated communities, hikers, and farmers a cheap, reliable messaging service far from cellphone towers. However, it is a move that some telecoms companies think could also interfere with their services, interrupt life-saving emergency calls and even cause outages nationwide. The roll-out will be a key test of the FCC’s ability to manage spectrum sharing, an innovation it is counting on to enable future 5G wireless and Internet of Things technologies.
Researchers covet terahertz waves for their ability to deliver data wirelessly at rates as high as 100 gigabits per second. That’s an unbelievably fast rate to achieve over the air, especially when you consider that: a) the average U.S. broadband speed is 55 megabits per second; and b) broadband service is piped into homes on fiber optic cables. For decades, academics have tried to develop terahertz-capable components to bring these exceedingly fast speeds to all of us. Researchers at Tufts University have developed a new terahertz modulator that is the first such device to fit on a chip.