In a world-first achievement published in ("An anisotropic hydrogel with electrostatic repulsion between cofacially aligned nanosheets"), scientists from the RIKEN Center for Emergent Matter Science in Japan, along with colleagues from the National Institute of Material Science and the University of Tokyo, have developed a new hydrogel whose properties are dominated by electrostatic repulsion, rather than attractive interactions. According to Yasuhiro Ishida, head of the Emergent Bioinspired Soft Matter Research Team, the work began from a surreptitious discovery, that when titanate nano-sheets are suspended in an aqueous colloidal dispersion, they align themselves face-to-face in a plane when subjected to a strong magnetic field. The field maximizes the electrostatic repulsion between them and entices them into a quasi-crystalline structure. They naturally orient themselves face to face, separated by the electrostatic forces between them. To create the new material, the researchers used the newly discovered method to arrange layers of the sheets in a plane, and once the sheets were aligned in the plane, fixed the magnetically induced structural order by transforming the dispersion into a hydrogel using a procedure called light-triggered in-situ vinyl polymerization. Essentially, pulses of light are used to congeal the aqueous solution into a hydrogel, so that the sheets could no longer move. By doing this, they created a material whose properties are dominated by electrostatic repulsion, the same force that makes our hair stand end when we touch a van generator. Up to now, manmade materials have not taken advantage of this phenomenon, but nature has. Cartilage owes its ability to allow virtually frictionless mechanical motion within joints, even under high compression, to the electrostatic forces inside it. Electrostatic repulsive forces are used in various places, such as maglev trains, vehicle suspensions and noncontact bearings, but up to now, materials design has focused overwhelmingly on attractive interactions. The resultant new material, which contains the first example of charged inorganic structures that align co-facially in a magnetic flux, has interesting properties. It easily deforms when shear forces are applied parallel to the embedded nano-sheets, but strongly resists compressive forces applied orthogonally. According to Ishida, "This was a surprising discovery, but one that nature has already made use of. We anticipate that the concept of embedding anisotropic repulsive electrostatics within a composite material, based on inspiration from articular cartilage, will open new possibilities for developing soft materials with unusual functions. Materials of this kind could be used in the future in various areas from regenerative medicine to precise machine engineering, by allowing the creation of artificial cartilage, anti-vibration materials and other materials that require resistance to deformation in one plane."
Review of studies on exotic superfluids in spin-orbit coupled Fermi gases
Ultracold atomic gases have been widely considered as ideal platforms for quantum simulation. Thanks to the clean environment and the highly tunable parameters in these systems, many interesting physical models can be simulated using cold atomic gases, and various novel many-body states have been prepared and probed experimentally. The recent experimental realization of synthetic gauge field in ultracold atomic gases has significantly extended the horizon of quantum simulation with cold atoms. As a special form of synthetic gauge field, synthetic spin-orbit coupling has attracted much attention recently. Professor YI Wei from University of Science and Technology of China, Professor ZHANG Wei from Renmin University of China, and Professor CUI Xiaoling from Chinese Academy of Sciences reviewed the recent theoretical studies on various novel pairing superfluid phases in spin-orbit coupled ultracold Fermi gases. They showed that spin-orbit coupling modifies the single-particle spectra, which gives rise to exotic few-body correlations and interesting pairing states. The review article was published in ("Pairing superfluidity in spin-orbit coupled ultracold Fermi gases"). 
Schematic illustration of the single-particle spectra modified by spin-orbit coupling. The Rashba-type spin-orbit coupling can lead to a degenerate ring in momentum space for the lower branch of the single-particle dispersion spectra (left). The lower-branch dispersion spectrum under the NIST-type spin-orbit coupling (right) is less symmetric. These differences, as well as the hyperfine-spin dependence of the single-particle dispersion under spin-orbit coupling, give rise to rich physics in these systems. (© Science China Press) In condensed-matter materials, spin-orbit coupling plays a key role in many interesting phenomena, such as quantum spin Hall effects, topological insulators, and topological superconductors. With the availability of synthetic spin-orbit coupling as a tool of quantum control, people hope to simulate various topological phases, the topological superfluid state in particular, in the highly controllable environment of ultracold Fermi gases. Indeed, recent theoretical studies have suggested that exotic superfluid phases and novel phenomena can be engineered with carefully designed configurations. By reviewing these theoretical studies, YI et al. discuss the exotic superfluid phases in systems with different spatial dimensions and with different forms of spin-orbit coupling. A fundamentally important effect of spin-orbit coupling is the modification of single-particle dispersion spectra. The review focuses on how this effect leads to interesting pairing phases such as the topological superfluid state, various gapless superfluid states, the spin-orbit-coupling-induced Fulde-Ferrell state, and the topological Fulde-Ferrell state. Besides many-body physics, the change in the single-particle dispersion can also induce novel few-body correlations, for example, a three-body bound state in the absence of any stable two-body bound state. These interesting few-body states, if observed, should no doubt give rise to even more exotic many-body properties.
Schematic illustration of the single-particle spectra modified by spin-orbit coupling. The Rashba-type spin-orbit coupling can lead to a degenerate ring in momentum space for the lower branch of the single-particle dispersion spectra (left). The lower-branch dispersion spectrum under the NIST-type spin-orbit coupling (right) is less symmetric. These differences, as well as the hyperfine-spin dependence of the single-particle dispersion under spin-orbit coupling, give rise to rich physics in these systems. (© Science China Press) In condensed-matter materials, spin-orbit coupling plays a key role in many interesting phenomena, such as quantum spin Hall effects, topological insulators, and topological superconductors. With the availability of synthetic spin-orbit coupling as a tool of quantum control, people hope to simulate various topological phases, the topological superfluid state in particular, in the highly controllable environment of ultracold Fermi gases. Indeed, recent theoretical studies have suggested that exotic superfluid phases and novel phenomena can be engineered with carefully designed configurations. By reviewing these theoretical studies, YI et al. discuss the exotic superfluid phases in systems with different spatial dimensions and with different forms of spin-orbit coupling. A fundamentally important effect of spin-orbit coupling is the modification of single-particle dispersion spectra. The review focuses on how this effect leads to interesting pairing phases such as the topological superfluid state, various gapless superfluid states, the spin-orbit-coupling-induced Fulde-Ferrell state, and the topological Fulde-Ferrell state. Besides many-body physics, the change in the single-particle dispersion can also induce novel few-body correlations, for example, a three-body bound state in the absence of any stable two-body bound state. These interesting few-body states, if observed, should no doubt give rise to even more exotic many-body properties.Introducing Graphene Study 2015
As part of its extensive education and outreach activities, Europe’s Graphene Flagship will soon stage a second Graphene Study week. This will take place from 23-28 March 2015 in Kaprun, a small town in the alpine Pinzgau region of Austria. 
Graphene Study brings together research students working on graphene and related two-dimensional materials with experienced scientists and engineers from academia and industry. In addition to formal lectures and poster sessions, Graphene Week provides participants with opportunities for networking and community building.
These four subject areas will be led by four eminent research leaders. Professor Vladimir Falko (Lancaster) is responsible for fundamental science, high-frequency electronics will be covered by Dr Daniel Neumaier (AMO, Aachen), optoelectronics by Professor Andrea Ferrari (Cambridge), and spintronics by Professor Bart van Wees (Groningen). The subject leaders will in turn invite a number of specialist lecturers active in their respective research areas. We envisage around 80 student participants in the Graphene Study 2015 week. There will be 30 hours of lectures, two poster sessions, and three mini-workshops, including sessions on peer-review publication and research grant applications. The cultural programme will feature a welcome reception, slalom skiing competition, and a Pecha Kucha night. You can think of the latter as karaoke for geeks! A few months following the Graphene Study 2015 school, video recordings of its lectures, together with other relevant documents, will be made available to all free of charge via the flagship website. Registration opened on 15 December, and the early-bird concession extends to 18 January. The normal registration deadline is 8 February, but in extenuating circumstances we can extend this to 22 February at the very latest. Graphene Study 2015 kicks off at 17:00 on Monday 23 March with an introductory lecture by the most esteemed Nobel laureate, Professor Sir Kostya Novoselov. This will be followed by a drinks reception and dinner. The school ends at lunchtime on Saturday 28 March, with the farewell dinner and party taking place on the Friday evening. All Graphene Study participants will be accommodated under one roof – that of the 3* Jufa youth hotel. The nearest airport is Salzburg, which is around 100 kilometres by road from Kaprun. Travel by private car is possible, and there is a direct bus service between Salzburg airport and Zell am See.
Graphene Study brings together research students working on graphene and related two-dimensional materials with experienced scientists and engineers from academia and industry. In addition to formal lectures and poster sessions, Graphene Week provides participants with opportunities for networking and community building.
DSC_0096Graphene Study is the flagship’s principal contribution to fostering the next generation of researchers working at the forefront of nanomaterials science and technology. Whilst the school is commissioned and organised by the Graphene Flagship, it is open to the graphene community within and without the flagship consortium.
Graphene Study 2015 will focus on four closely related topics:
- – Fundamental science of 2D materials
- – High-frequency electronics
- – Optoelectronics
- – Spintronics
These four subject areas will be led by four eminent research leaders. Professor Vladimir Falko (Lancaster) is responsible for fundamental science, high-frequency electronics will be covered by Dr Daniel Neumaier (AMO, Aachen), optoelectronics by Professor Andrea Ferrari (Cambridge), and spintronics by Professor Bart van Wees (Groningen). The subject leaders will in turn invite a number of specialist lecturers active in their respective research areas. We envisage around 80 student participants in the Graphene Study 2015 week. There will be 30 hours of lectures, two poster sessions, and three mini-workshops, including sessions on peer-review publication and research grant applications. The cultural programme will feature a welcome reception, slalom skiing competition, and a Pecha Kucha night. You can think of the latter as karaoke for geeks! A few months following the Graphene Study 2015 school, video recordings of its lectures, together with other relevant documents, will be made available to all free of charge via the flagship website. Registration opened on 15 December, and the early-bird concession extends to 18 January. The normal registration deadline is 8 February, but in extenuating circumstances we can extend this to 22 February at the very latest. Graphene Study 2015 kicks off at 17:00 on Monday 23 March with an introductory lecture by the most esteemed Nobel laureate, Professor Sir Kostya Novoselov. This will be followed by a drinks reception and dinner. The school ends at lunchtime on Saturday 28 March, with the farewell dinner and party taking place on the Friday evening. All Graphene Study participants will be accommodated under one roof – that of the 3* Jufa youth hotel. The nearest airport is Salzburg, which is around 100 kilometres by road from Kaprun. Travel by private car is possible, and there is a direct bus service between Salzburg airport and Zell am See.
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