Imec and its partners announced today that they have successfully completed a three-year program (2012 - 2015) to leverage a variety of silicon photonics technologies by making them accessible for industry and academia worldwide. Within the ESSenTIAL program funded by the European Commission, imec has worked closely with CEA-LETI (France), Tyndall Institute (Ireland), VTT (Finland), IHP (Germany), TNO (The Netherlands) and CMC (Canada) to develop advanced multi-project-wafer services as well as packaging services for silicon photonics. The services were made accessible to industrial players – both small- and medium-sized companies – enabling them to test silicon photonics technology. Silicon photonics is a key enabling technology for a wide range of markets, from optical interconnect networks in data centers to disposable biosensor chips for immunoassays. In essence, silicon photonics builds on the technology portfolio and economy of scale of CMOS fabs to manufacture sophisticated photonic integrated circuits with a combination of passive devices – in particular wavelength and polarisation selective devices – and active devices such as optical modulators and detectors. The ESSenTIAL program has extensively expanded the services of ePIXfab, an alliance of European entities set up in 2006 to support the emergence of a fabless silicon photonics ecosystem. ePIXfab has provided affordable Multi-Project Wafer (MPW) services to fabless R&D teams worldwide developing photonic circuits. European users received some benefits based on EU funding, but the ePIXfab services were provided globally. “ePIXfab was founded to provide the silicon photonics research community an access path to advanced CMOS technology with the goal of sharing cost and expertise. ePIXfab has helped to accelerate the field of silicon photonics and to let it move from a research field to a field of critical industrial importance,” says Ghent University professor Roel Baets, one of the founders of ePIXfab and research team leader associated with imec. Within the ESSenTIAL project, the portfolio of silicon photonics services offered by ePIXfab has been extended in many ways. High speed active devices (up to 25 Gbit/s) were added to the MPW offering. Furthermore, ePIXfab has started to organize extra MPW runs on two silicon photonics technology platforms with special unique features, at IHP and at VTT. In total over 200 silicon photonics circuit designs were prototyped at imec, LETI, IHP or VTT, including close to 50 designs from companies. Another major achievement of the project was the creation of silicon photonics packaging services at Tyndall Institute. ”Packaging is often seen as the Achilles heel of photonic component technology. Tyndall Institute has developed a family of solutions, encompassing optical, electrical and RF packaging. These standardized packaging approaches for silicon photonic chips are available to industry through the ePIXfab-alliance”, stated Peter O’Brien, Head of the Photonics Packaging Group at Tyndall. Given the shortage of skilled engineers in silicon photonics, especially at the design level, ESSenTIAL has spent considerable resources on training activities. Over 110 experts were trained in regular six-monthly training events and several hundreds more were reached through webinars. Last but not least, ESSenTIAL has conducted 80 feasibility studies with European SMEs, which resulted in at least 22 new projects and over 30 project proposals. During ESSenTIAL the MPW operation for silicon photonics has been integrated into Europractice IC service, marking a milestone for the further growth of Europe’s silicon photonics. “Through the EUROPRACTICE service, more than 650 European academia and 300 companies world-wide have now access to Si Photonics technologies” says Carl Das, Chairman of the Europractice service. While the MPW-services for silicon photonics are open to any company, research institute or university, it is worth mentioning that there are financially attractive options for European small and medium-sized companies to develop a silicon photonics prototype in the context of their product innovation. This is possible through the EU-funded project ACTPHAST.
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New lithium ion battery is safer, tougher, and more powerful
Lithium ion batteries (LIBs) are a huge technological advancement from lead acid batteries which have existed since the late 1850’s. Thanks to their low weight, high energy density and slower loss of charge when not in use, LIBs have become the preferred choice for consumer electronics. Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four-times that of lead acid. Despite being a superior consumer battery, LIBs still have some drawbacks. Current manufacturing technology is reaching the theoretical energy density limit for LIBs and overheating leading to thermal runaway i.e. “venting with flame” is a serious concern. South Korean researchers at the Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Department of Chemistry and Division of Advanced Materials Science at Pohang University, have created a new LIB made from a porous solid which greatly improves its performance as well as reducing the risks due to overheating ("Solid lithium electrolytes based on an organic molecular porous solid"). ![incorporation of various lithium precursor to porous CB[6]](https://lh3.googleusercontent.com/blogger_img_proxy/AEn0k_tqGRb7tlmyuDoCq97Z6FM8n6QOt0J9yfsrmupwDtgJJEHagBSEg-1cdwHpUDJiMVibsvo0nRUU=s0-d)
Simple incorporation of various lithium precursor to porous CB[6] exhibits high lithium ion conductivities, mobility and safer dried solid lithium electrolytes. Since 2002 there have been over 40 recalls in the US alone due to fire or explosion risk from LIBs used in consumer electronic devices. These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics despite their poor track record at high temperatures. The Korean team tried a totally new approach in making the batteries. According to Dr. Kimoon Kim at IBS, “we have already investigated high and highly anisotropic [directionally dependent] proton conducting behaviors in porous CB[6] for fuel cell electrolytes. It is possible for this lithium ion conduction following porous CB[6] to be safer than existing solid lithium electrolyte -based organic-molecular porous-materials utilizing the simple soaking method.” Current LIB technology relies on intercalated lithium which functions well, but due to ever increasing demands from electronic devices to be lighter and more powerful, investigation of novel electrolytes is necessary in order. The new battery is built from pumpkin-shaped molecules called cucurbit[6]uril (CB[6]) which are organized in a honeycomb-like structure. The molecules have an incredibly thin 1D-channel, only averaging 7.5 Å [a single lithium ion is 0.76 Å, or .76 x 10-10 m] that runs through them. The physical structure of the porous CB[6] enables the lithium ions to battery to diffuse more freely than in conventional LIBs and exist without the separators found in other batteries. In tests, the porous CB[6] solid electrolytes showed impressive lithium ion conductivity. To compare this to existing battery electrolytes, the team used a measurement of the lithium transference number (tLi+) which was recorded at 0.7-0.8 compared to 0.2-0.5 of existing electrolytes. They also subjected the batteries to extreme temperatures of up to 373 K (99.85° C), well above the 80° C typical upper temperature window for exiting LIBs. In the tests, the batteries were cycled at temperatures between 298 K and 373 K ( 24.85° C and 99.85° C) for a duration of four days and after each cycle the results showed no thermal runaway and hardly any change in conductivity. Various conventional liquid electrolytes can incorporate in a porous CB[6] framework and converted to safer solid lithium electrolytes. Additionally, electrolyte usage is not limited to use only in LIBs, but a lithium air battery potentially feasible. What makes this new technique most exciting is that it is a new method of preparing a solid lithium electrolyte which starts as a liquid but no post-synthetic modification or chemical treatment is needed.
read more "New lithium ion battery is safer, tougher, and more powerful"
Simple incorporation of various lithium precursor to porous CB[6] exhibits high lithium ion conductivities, mobility and safer dried solid lithium electrolytes. Since 2002 there have been over 40 recalls in the US alone due to fire or explosion risk from LIBs used in consumer electronic devices. These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics despite their poor track record at high temperatures. The Korean team tried a totally new approach in making the batteries. According to Dr. Kimoon Kim at IBS, “we have already investigated high and highly anisotropic [directionally dependent] proton conducting behaviors in porous CB[6] for fuel cell electrolytes. It is possible for this lithium ion conduction following porous CB[6] to be safer than existing solid lithium electrolyte -based organic-molecular porous-materials utilizing the simple soaking method.” Current LIB technology relies on intercalated lithium which functions well, but due to ever increasing demands from electronic devices to be lighter and more powerful, investigation of novel electrolytes is necessary in order. The new battery is built from pumpkin-shaped molecules called cucurbit[6]uril (CB[6]) which are organized in a honeycomb-like structure. The molecules have an incredibly thin 1D-channel, only averaging 7.5 Å [a single lithium ion is 0.76 Å, or .76 x 10-10 m] that runs through them. The physical structure of the porous CB[6] enables the lithium ions to battery to diffuse more freely than in conventional LIBs and exist without the separators found in other batteries. In tests, the porous CB[6] solid electrolytes showed impressive lithium ion conductivity. To compare this to existing battery electrolytes, the team used a measurement of the lithium transference number (tLi+) which was recorded at 0.7-0.8 compared to 0.2-0.5 of existing electrolytes. They also subjected the batteries to extreme temperatures of up to 373 K (99.85° C), well above the 80° C typical upper temperature window for exiting LIBs. In the tests, the batteries were cycled at temperatures between 298 K and 373 K ( 24.85° C and 99.85° C) for a duration of four days and after each cycle the results showed no thermal runaway and hardly any change in conductivity. Various conventional liquid electrolytes can incorporate in a porous CB[6] framework and converted to safer solid lithium electrolytes. Additionally, electrolyte usage is not limited to use only in LIBs, but a lithium air battery potentially feasible. What makes this new technique most exciting is that it is a new method of preparing a solid lithium electrolyte which starts as a liquid but no post-synthetic modification or chemical treatment is needed.
A surprisingly simple magnetic flip
A RIKEN-led research team has stumbled on a remarkably simple way to flip the magnetic orientation of mirror-image magnetic domains in the unusual magnetic material pyrochlore ("All-In–All-Out Magnetic Domains: X-Ray Diffraction Imaging and Magnetic Field Control"). This flipping technique also makes it possible to observe these domains precisely in real space, providing a new tool for exploring spin-based device applications. 
A new technique that applies different combinations of magnets to an osmium-based crystal can ‘flip’ regions of magnetic spin from one orientation to another (pink and green shading). Pyrochlore crystals have attracted the attention of physicists because of their unusual magnetic potential. These crystals consist of tetrahedral crystal units, where the electron spins at the four vertices are in a constant state of magnetic ‘frustration’ that results in multiple magnetic ground states. Recently, researchers found evidence of ‘all-in/all-out’ configurations in pyrochlore lattices, where all four spins either point toward the center of the tetrahedron or away from it (Fig. 1). This arrangement breaks the magnetic frustration and produces only two ground states that are related by time-reversal symmetry. However, distinguishing the two types of magnetic domains is tricky because the all-in/all-out magnetic structure is an antiferromagnetic arrangement that does not respond to typical electronic and magnetic probes. Taka-hisa Arima and his colleagues from the RIKEN SPring-8 Center and RIKEN Center for Emergent Matter Science, in collaboration with researchers from across Japan, realized that one way to spot these elusive twin domains is to examine the resonant scattering signal from polarized x-rays. In this technique, the energy of the incident x-ray can be tuned to resonate with a specific site, element or electronic transition of a material, making the technique ideal for locating magnetic symmetry transitions. By measuring the changes induced by right- and left-handed circularly polarized light using a low-temperature microdiffraction technique, the team deduced a ‘flipping ratio’ that identifies the local magnetic domain orientations. When the researchers measured the flipping ratios of pyrochlore crystals of cadmium-osmium oxide (Cd2Os2O7) at the SPring-8 synchrotron radiation facility, they found that the domain structures were significantly affected just by cooling a sample near a permanent magnet. The existence of such a simple, reversible and controllable way to manipulate spins was a surprise. “Because the all-in/all-out structure cannot host any magnetization, almost no-one predicted that its magnetic domain could be controlled by a magnetic field,” notes Arima. The researchers also suggest that this technique can image and control any type of pyrochlore with an all-in/all-out structure—not just Cd2Os2O7. “Recent theories predict that iridium oxide pyrochlore might have exotic electronic states along magnetic domain walls, as well as on its surface,” says Arima. “Our technique could provide quite useful information about these systems.”
read more "A surprisingly simple magnetic flip"
A new technique that applies different combinations of magnets to an osmium-based crystal can ‘flip’ regions of magnetic spin from one orientation to another (pink and green shading). Pyrochlore crystals have attracted the attention of physicists because of their unusual magnetic potential. These crystals consist of tetrahedral crystal units, where the electron spins at the four vertices are in a constant state of magnetic ‘frustration’ that results in multiple magnetic ground states. Recently, researchers found evidence of ‘all-in/all-out’ configurations in pyrochlore lattices, where all four spins either point toward the center of the tetrahedron or away from it (Fig. 1). This arrangement breaks the magnetic frustration and produces only two ground states that are related by time-reversal symmetry. However, distinguishing the two types of magnetic domains is tricky because the all-in/all-out magnetic structure is an antiferromagnetic arrangement that does not respond to typical electronic and magnetic probes. Taka-hisa Arima and his colleagues from the RIKEN SPring-8 Center and RIKEN Center for Emergent Matter Science, in collaboration with researchers from across Japan, realized that one way to spot these elusive twin domains is to examine the resonant scattering signal from polarized x-rays. In this technique, the energy of the incident x-ray can be tuned to resonate with a specific site, element or electronic transition of a material, making the technique ideal for locating magnetic symmetry transitions. By measuring the changes induced by right- and left-handed circularly polarized light using a low-temperature microdiffraction technique, the team deduced a ‘flipping ratio’ that identifies the local magnetic domain orientations. When the researchers measured the flipping ratios of pyrochlore crystals of cadmium-osmium oxide (Cd2Os2O7) at the SPring-8 synchrotron radiation facility, they found that the domain structures were significantly affected just by cooling a sample near a permanent magnet. The existence of such a simple, reversible and controllable way to manipulate spins was a surprise. “Because the all-in/all-out structure cannot host any magnetization, almost no-one predicted that its magnetic domain could be controlled by a magnetic field,” notes Arima. The researchers also suggest that this technique can image and control any type of pyrochlore with an all-in/all-out structure—not just Cd2Os2O7. “Recent theories predict that iridium oxide pyrochlore might have exotic electronic states along magnetic domain walls, as well as on its surface,” says Arima. “Our technique could provide quite useful information about these systems.”
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