Dan Cohen AUTHOR The success of the Air Force Research Laboratory (AFRL) at Wright-Patterson Air Force Base would not be possible without the contribution of the defense industry — including the small business community — and academic partners in western Ohio, AFRL Commander Maj. Gen. Tom Masiello said at the Dayton Development Coalition’s annual meeting earlier this week.“I don’t know if it’s in the water here, but there’s something special that you have here,” Masiello told attendees.AFRL outsources about 75 percent of its annual $4 billion budget to industry, universities and global allies, reported the Dayton Daily News. About half of AFRL’s 10,000 workers and five of its technology directorates are housed at the base located outside of Dayton.“Your DNA is all about innovation, which really helps our mission,” Masiello said.Of course, the link between the lab and its industry partners is not just a one-way street; the Dayton region has benefitted tremendously from the work at Wright-Patterson.AFRL and its partners generated $569 million in new capital investment last year in a 12-county region in western Ohio, according to the Dayton Development Coalition. That investment created 3,136 jobs and retained 11,131 existing jobs. New payroll reached $139 million.Coalition President and CEO Jeff Hoagland, meanwhile, warned the audience that the Dayton community shouldn’t get complacent about the oversized role Wright-Patterson plays in the region, according to the story.“Please do not forget the word BRAC,” he said. “I know people do not like that word. But it’s the truth,” said Hoagland, who predicted a new round would go ahead at some point.
Figure 2 | AFM and piezoresponse images of CIPS with different thicknesses. (a–c) AFM topography (a) PFM amplitude (b) and PFM phase (c) for CIPS flakes ranging from 100 to 7 nm thick, on doped Si substrate. Scale bar in a, 1 μm. (d,e) AFM topography (d) PFM amplitude (e) and phase (f) of 2–4 layer thick CIPS on Au coated SiO2/Si substrate. Scale bar in d, 500 nm. (g) the height (black) and PFM amplitude (blue) profile along the lines shown in d and e, respectively. L, Layers. Credit: Liu F, et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nature Communications 7, Article number: 12357 (2016). Copyright © 2016, Rights Managed by Nature Publishing Group. Creative Commons Attribution 4.0 International License. Wang describes the ways in which the researchers addressed these challenges. “To characterize ferroelectricity at nanoscale, the most widely used technique is called piezoresponse force microscopy, or PFM, which utilizes the converse piezoelectric effect.” (In the converse piezoelectric effect, materials become strained when an electric field is applied.) This is a technique that can be implemented using a commercially available atomic force microscope (AFM), in which AC bias can be applied to the AFM probe that serves as a moving electrode on top of the sample. The resulting AC electric field will cause the periodic oscillation of the ferroelectric sample due to this converse piezoelectric effect. The oscillation signal can then be detected by the AFM. “The amplitude of the oscillation represents the piezoelectric response that is proportional to the ferroelectric polarization,” Wang explains, “while the phase of the oscillation represents the direction of the polarization.” In their study, the scientists employed a state-of-the-art approach known as Dual AC Resonance Tracking (DART) PFM developed by Asylum Research to amplify the piezoelectric response by taking advantage of the resonance enhancement. The scientists are planning to study the pyroelectric properties of CuInP2S6 at its two-dimensional limit and apply their findings to developing energy harvesting devices. To that end, he adds, because mechanically exfoliated 2D materials are usually small and unsuitable for device applications, chemical vapor deposition growth of atomically thin CuInP2S6 is under development.”Ferroelectric properties are also very interesting for solar cell applications because of efficient ferroelectric polarization-driven carrier separation,” Liu concludes, “so 2D ferroelectricity-based solar cells could be very interesting, In its liquid phase, 2D ferroelectric CuInP2S6 could be easily hybridized with semiconductor 2D or organic materials – and a solar cell based on these hybrids would be very promising.” Figure 5 | Electric characterization of the vdW CIPS/Si diode. (a) The I–V curves from the typical vdW CIPS/Si diode with 30 nm thick CIPS, by sweeping the bias from 2.5 to −2.5 V, and then back to 2.5 V. Inset is the schematic of the device. (b) Resistance-switching voltage hysteresis loop of the diode measured at a bias voltage of −1.3 V. The schematic representations of the ON and OFF states with respect to the polarization direction are shown in the bottom-left and top-right insets, respectively. (c) Out-of-plane PFM amplitude (black) and phase (blue) measurements on the same diode device shown in a. Credit: Fucai Liu, Lu You, Kyle L. Seyler, Xiaobao Li, Peng Yu et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nature Communications 7, Article number: 12357 (2016). Copyright © 2016, Rights Managed by Nature Publishing Group. Creative Commons Attribution 4.0 International License. Journal information: Nature Communications More information: Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes, Nature Communications 7, Article number: 12357 (2016), doi:10.1038/ncomms12357Related:1. Subatomic deformation driven by vertical piezoelectricity from CdS ultrathin films, Science Advances 01 Jul 2016, Vol. 2, no. 7, e1600209, doi:10.1126/sciadv.16002092. Picoscale precision though ultrathin film piezoelectricity, Phys.org (10 August 2016), https://sp2.img.hsyaolu.com.cn/wp-shlf1314/2020/IMG14551.jpg” alt=”center_img” /> Figure 1 | Crystal structure and characterization of CIPS. (a,b) The side view (a) and side view (b) for the crystal structure of CIPS (CuInP2S6) with vdW gap between the layers. Within a layer, the Cu, In and P–P form separate triangular networks. The polarization direction is indicated in by the arrow. (b) The ferroelectric hysteresis loop of a 4-μm-thick CIPS flake. (c) AFM image of the CIPS flakes with different thicknesses. Scale bar, 2 μm. (d) The height profile along the line shown in c. Clear step height of 0.7 nm corresponding to single layer thickness of CIPS can be observed. L, Layers. Credit: Liu F, et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nature Communications 7, Article number: 12357 (2016). Copyright © 2016, Rights Managed by Nature Publishing Group. Creative Commons Attribution 4.0 International License. (Phys.org)—Optoelectronic devices that combine electronics and photonics are incorporating two-dimensional (2D) materials for a range of applications. At the same time, cooperative phenomena – in which a system’s individual components appear to act as a single entity rather than independently – have yet to be widely investigated, an important example being ferroelectricity (spontaneous electric polarization that can be reversed by an electric field) in the 2D limit. Recently, however, scientists at Nanyang Technological University, Singapore have demonstrated room-temperature out-of-plane ferroelectricity (that is, orthogonal to the 2D material) in 2D CuInP2S6 (copper indium thiophosphate) with a ~320 K transition temperature, as well as switchable polarization in 4 nm CuInP2S6 flakes. The researchers state that their findings create the possibility of sensors, actuators, non-volatile memory devices, various van der Waals heterostructures (devices made from layers of dissimilar 2D crystals in which forces are based on molecular attraction or repulsion rather than covalent or ionic bonds), and other novel applications based on 2D ferroelectricity. Finally, in demonstrating a non-volatile memory device with an on/off ratio of ~100 in a CuInP2S6/Si ferroelectric diode, Liu notes that this investigation is just a preliminary demonstration of the possible applications of the 2D ferroelectric material. “A lot of work needs to be done to fully understand the transport mechanisms and how it is coupled to the ferroelectric switching,” he acknowledges. Tunable and mechanically robust ferroelectric ionic plastic crystals Prof. Zheng Liu and Prof. Junling Wang discussed the challenges that they and their colleagues encountered in conducting their study published in Nature Communications. “With reduced dimension, ferroelectricity – namely, long-range electric-dipole order – becomes fragile owing to the depolarization field that is opposing its own electric polarization,” Liu tells Phys.org. “The depolarization field inherently arises in ferroelectric materials due to the imperfect screening of bound charges,” that is, those bound to molecules and so cannot move in response to an external electromagnetic force. The difficulty lies in maintaining a precise geometry, Liu adds, because when the ferroelectric material’s thickness is reduced to its two-dimensional limit, the depolarization field can increase by orders of magnitude. At that point, the depolarization field may place the ferroelectric material into a paraelectric state, the result being disordered electric dipoles with a temporary polarization only when in the presence of an electric field. Therefore, the electrical boundary conditions are extremely important when exploring ferroelectricity at the material’s 2D limit. Moreover, he adds, reporting the experimental observation of switchable polarization in CuInP2S6 films down to 4 nm at room temperature, thickness reduction will greatly weaken the out-of-plane ferroelectric polarization. “This makes characterization of the ferroelectricity very difficult. Moreover, the large ionic conductivity of this material makes the polarization switching quite challenging. We therefore had to choose a small electric field that is just above the coercive field to avoid unwanted ionic motion.”Other concerns include demonstrating the potential of this 2D ferroelectric material by preparing a van der Waals ferroelectric diode formed by CuInP2S6/Si heterostructure. “In the case of CuInP2S6, the chemical composition and phase stability also play a role in stabilizing ferroelectric states – and in the 2D limit, it is difficult to determine the ferroelectricity with traditional methods, such as the time-dependent ferroelectric hysteresis loop measurement, due to large leakage current,” lead author Liu Fucai points out. Regarding potential, he explains that due to the relatively large band gap and thus weak light absorption, few-layer CuInP2S6 appears almost transparent on silicon (Si) substrate. “This situation makes the fabrication of the van der Waals heterostructure quite challenging during the lithography process.” Figure 3 | Ferroelectric polarization switching by PFM for CIPS flakes with different thicknesses. (a) The I–V curves from the typical vdW CIPS/Si diode with 30 nm thick CIPS, by sweeping the bias from 2.5 to −2.5 V, and then back to 2.5 V. Inset is the schematic of the device. (b) Resistance-switching voltage hysteresis loop of the diode measured at a bias voltage of −1.3 V. The schematic representations of the ON and OFF states with respect to the polarization direction are shown in the bottom-left and top-right insets, respectively. (c) Out-of-plane PFM amplitude (black) and phase (blue) measurements on the same diode device shown in a. Credit: Fucai Liu, Lu You, Kyle L. Seyler, Xiaobao Li, Peng Yu et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nature Communications 7, Article number: 12357 (2016). Copyright © 2016, Rights Managed by Nature Publishing Group. Creative Commons Attribution 4.0 International License. “By driving the AC field at the first harmonic contact resonance,” Wang continues, “the piezoelectric oscillation signal can be greatly enhanced. Thus, the small ferroelectric polarization of the ultrathin CuInP2S6 flakes can still be detected by the AFM, as the signal has been amplified by orders of magnitude. This advanced PFM technique helps us to image the fine domain structure with nanometer lateral resolution and picometer vertical resolution, and thereby realize local ferroelectric switching using an AFM probe.”The paper discusses novel applications, including sensors, actuators, non-volatile memory devices, and various van der Waals heterostructures based on 2D ferroelectricity. “By virtue of the piezoelectric effect, ferroelectric materials always have the piezoelectric and pyroelectric properties that allow the use of atomically-thin CuInP2S6 as a strain sensor with high flexibility, such as electric skin monitoring human body motion,” Liu tells Phys.org. “By using the pyroelectric effect, 2D CuInP2S6 could also be used for thermal energy harvesting, and as we know, commercially available ferroelectric random access memory, or FeRAM” – random-access memory similar to DRAM – “with fast writing speed and low-power consumption, but with destructive readout could be improved by employing a ferroelectric diode to achieve non-destructive readout of the information. Considering the quasi-freestanding nature of 2D materials, ferroelectric diodes, or even ferroelectric tunnel junctions with an atomically thin ferroelectric layer may have a much higher ON/OFF ratio, providing the possibility of high-density ferroelectric memories with non-destructive readout.”Regarding the relationship between, and potential applications deriving from, ferro- and piezoelectric effects and van der Waals heterostructure interactions, Liu notes that vertically stacking of different 2D materials with van der Waals force have revealed unusual properties and have been investigated for the application of tunneling transistors, light emitting diodes, and light harvesting devices. “Incorporating ferroelectricity to the van der Waals heterostructure could demonstrate new functionality, such as ferroelectric field transistors and optoelectronic memory, by combining CuInP2S6 with 2D semiconductors.” © 2016 Phys.org
Kolkata: Mystery shrouds the death of an elderly woman and her daughter whose charred bodies were found inside their apartment in Dum Dum on Friday evening.Police said the victims, identified as Dipti Mukherjee (72) and her daughter Sathi Mukherjee (54) were alone in the flat when the incident happened. Police suspect after preliminary investigation that fire from the gas cylinder led to their death but it is yet to be discovered as to how the charred bodies reached the bedroom. The police have initiated an unnatural death case in this connection and are trying to find out the exact reason. Also Read – Rain batters Kolkata, cripples normal lifeA police officer said that a plumber, who was working in another flat, noticed smoke billowing out of the victims’ flat on the first floor of a multi-storeyed building in the housing complex. The incident took place at around 5.30 pm on Friday. He informed others and the state Fire and Emergency Service department was contacted. Fire fighters reached the spot and broke open the door of the flat to find the charred bodies. The bodies have been sent for an autopsy. Police came to know that three persons — Sathi, her husband and her mother — used to live in the flat. Sathi’s husband was not in the flat when theincident took place.
June 14, 2010 6 min read Register Now » This story appears in the June 2010 issue of Entrepreneurs StartUps Magazine. Subscribe » 9. Verizon MiFi 2200 Intelligent Mobile Hotspot ($50)Staying connected to the Web on the road can be obscenely expensive: Expect to part with north of $700 for year-long data access fees. But relying on third-party hotspots and hotel WiFi is a recipe for disaster. So bite the bullet and get a mobile data plan. But instead of going with an old-school USB or modem card to get online, use this slick portable hotspot from Verizon. The MiFi takes cellular access and makes it into a local WiFi hotspot you can share. Though other carriers like Sprint have similar mobile offerings, Verizon can sell you mobile data by the week or month, which really takes out the sting of access fees. TIP: Look for promising contacts in airports and be generous: offer to share your access.10. Ultimate Ears MetroFi 170vi headphones ($60)No matter what mobile phone you get, first-quality, old-school wired ear buds and a mic are the single best thing you can get to improve voice quality, hear your tunes as they were recorded and otherwise do your best to avoid brain cancer. The pick right now for in-ear headphones is the Ultimate Ears MetroFi 170svi. The most rewarding $60 you’ll probably ever spend.11. Clickfree C2 Portable BackUp 250 GB ($120)Fail to back up your data at your own peril. Considering how idiot-proof hardware like Clickfree makes backing up your stuff, there is just no excuse for going unprotected. Simply plug in this small portable device to your computer, do what it tells you to do and repeat every week or so. Trust us, you’ll save yourself a world of hurt.12. WowWee Cinemin Swivel Pico Projector ($260)Every dreamer needs a great way to sell that dream. This is it. Turn it on, jack it into the output of your new laptop, iPhone or BlackBerry, and project your Powerpoint, video presentation or stills on any wall. Yup, that means the office wall, bar wall or elevator wall become your own private sales zone. And how cool to show up for the big pitch without having to mess with that clunky, old projector. Pulling this out of your pocket–it’s about the size of a cigarette pack–is a stylish and effective way to get your message across. 8. Apple iPhone 3G ($99) or BlackBerry Bold 9700 Refurb (free)If your business life is all about the app-based product, by all means Go iPhone. Nobody, not Android or Windows 7, can touch that. But if yours is a text-oriented, keyboard shop, you want BlackBerry–specifically, the Bold 9700. It’s big, fast and works with everything. The great part is, you can make this call at one store: AT&T. The old Ma Bell sells both the iPhone and is offering a great small-biz deal: refurbished 9700’s for the price of a contract. Try them both. See what feels best and go with it. 3. Google Apps and OpenOffice productivity software suites (free)Google Apps and OpenOffice do not come anywhere near Microsoft Office in terms of features–Excel devotees, in particular, will lose their minds on Google Docs Spreadsheets. But when combined, these two programs have many virtues. They offer powerful collaboration tools and get your shop working on the Internet cloud. Be sure to allow some training time: Some things, like document collaboration, are better done with Google; others, like document layout and tricky calculations, are more suited on OpenOffice. There is no better deal in small business tech right now.4. Acer X203H 20 Inch Wide Monitor ($120)Why pay a lot for idiot-proof stuff like monitors? No need. For a measly $120 you get a legit 20-inch imaging device that plugs right into your new Dell. Your new big screen eases eye strain, improves posture and, alas, lengthens your work day.5. Epson WorkForce 610 All-In-One Printer ($199)For the full on, max sense of the absurd value in today’s tech dollar, look no further than desktop imaging. Makers like HP, Brother and Samsung all offer great, low cost products, but for the startup, we give the nod to Epson. Not only fast and cheap, Epson excels in image quality on the printed page. For about the price of taking the family out for a ballgame, you get a near-professional-quality printing, scanning, faxing and copying device. And with a bit of trial and error you really can create business-quality cards, envelopes and brochures. Ridiculously powerful. Caveat: Watch your ink consumption. Replacement cartridges will kill you.6 &7. Microsoft Arc Keyboard ($60) and Gyration Air Mouse ($80)Your spiffy office would not be complete without a quality keyboard/mouse combo that reduces hand strain, increases productivity and lets you wow ’em come presentation time. Though it gets no street cred, Microsoft is doing sterling work with its comfy Arc keyboards. And Gyration is the leader in air mouses that need no desk (just point it at the screen). You’ll grow to love it. 1. Humanscale Diffrient World Mesh Back Task Chair (starting at $600)New York-based Humanscale, a high-end maker of office products, has worked hard to bring some of its best chairs within reach of small budgets. For our money–and yours, considering how much time you will spend in that command position– the Diffrient World line (named for designer Nils Diffrient) is the right balance of ergonomics, good looks and value. At this price, it’s a bargain. And your back will thank us. 2. Dell Vostro 1015 Notebook PC ($450)Fear not, Mac heads: You will get your Steve Jobs style points when we get to smart phones; but the fact is, burning three quarters of your budget on a MacBook makes no sense, when a mere $450 buys an awesome notebook from Dell–a basic black, 15-inch Dell Vostro running Windows 7 Home Premium. Skip the Microsoft Office software and instead get a free Google Apps account (more on that later). And stay away from fancy memory upgrades, beefier processors or extended service plans. Eventually, you will need to upgrade to a better PC and Microsoft Office as you grow. But for now keep it cheap, fast and simple. Free Webinar | Sept. 9: The Entrepreneur’s Playbook for Going Global Growing a business sometimes requires thinking outside the box. Welcome to the golden age of small business technology. If the grueling Great Recession has a silver lining, it’s this: Tech vendors are innovating and discounting. From furnishings to computers to mobile devices, consumer electronics have never offered the start-up enterprise more for less. What it used to cost for a computer, printer and some software will now get the savvy entrepreneur an entire office. So if you’re ready to start that business, you owe it to yourself to check out these 12 essentials, all for about two grand.