Nanowerk February 19, 2022 The size and adequate energy storage mismatch between microbatteries and microelectronics has emerged as a fundamental barrier against the take-off of tiny intelligent systems requiring power anytime anywhere. The on-chip self-assembly process known as micro-origami is capable of winding stacked thin films into Swiss-roll structures to reduce the footprint area, which exactly mimics the manufacture of the most successful full-sized batteries—cylinder batteries. In addition to discussing in detail the technical difficulties of reducing the size of on-chip microbatteries with various structures and potential solutions, researchers in Germany highlight the following two basic requirements for eventual integration […]
Tag Archives: S&T Germany
Nanowires under tension create the basis for ultrafast transistors
Phys.org February 7, 2022 Researchers in Germany produced nanowires consisting of a gallium arsenide core and an indium aluminum arsenide shell. The different chemical ingredients resulted in the crystal structures in the shell and the core having slightly different lattice spacings. This causes the shell to exert a high mechanical strain on the much thinner core changing the electronic properties of gallium arsenide in the core. They demonstrated that the strain in lattice-mismatched core/shell nanowires can affect the effective mass of electrons in a way that boosts their mobility to distinct levels. The electrons inside core of nanowires exhibited mobility […]
Self-organization of complex structures: a matter of time
Nanowerk January 19, 2022 Self-organization is a central feature of biological systems. Researchers in Germany have developed an approach based on the concept of time complexity, which allows new strategies to be created for the more efficient synthesizing of complex structures. They showed that different control scenarios can informatively be characterized by their time complexity, i.e., their scaling of the assembly time with the structure size, analogous to algorithms for computational problems. Especially for large structures, differences in the time complexity of the scenarios lead to strongly diverging time efficiencies. Most significantly, they showed that by effectively regulating the supply […]
Fingers made of laser light: Controlled grabbing and rotation of biological micro-objects
Science Daily December 23, 2021 Although optical trapping forces are strong enough and related photodamage is acceptable, the precise (re-) orientation of large specimen with multiple optical traps is difficult, since they grab blindly at the object and often slip off. Researchers in Germany have developed an approach to localize and track regions with increased refractive index using several holographic optical traps with a single camera in an off-focus position. They estimated the 3D grabbing positions around several trapping foci in parallel through analysis of the beam deformations, which are continuously measured by defocused camera images of cellular structures inside […]
‘Nano-chocolates’ that store hydrogen
Science Daily December 27, 2021 Storing hydrogen is costly. Researchers in Germany proposed storing hydrogen in palladium nanoparticles. To ensure that the tiny particles are sufficiently sturdy, they are stabilized by a core made of the rare precious metal iridium and attached to a graphene support. They are attached at intervals of two and a half nanometres resulting in a regular, periodic structure. When the palladium particles come into contact with hydrogen, hydrogen sticks to the nanoparticles’ surfaces, with hardly any of it penetrating inside. A small amount of heat is added to release hydrogen from the surface of the […]
New materials for quantum technologies
Phys.org December 22, 2021 To advance spintronics devices and quantum information technology using materials with non-trivial topological properties, three key challenges are still unresolved – the identification of topological band degeneracies located at the Fermi level, the ability to easily control such topological degeneracies., and the identification of generic topological degeneracies in large, multisheeted Fermi surfaces. Researchers in Germany have shown that the non-symmorphic symmetries in chiral, ferromagnetic manganese silicide (MnSi) generate nodal planes (NPs) which enforce topological protectorates (TPs) with substantial Berry curvatures at the intersection of the NPs with the Fermi surface (FS) regardless of the complexity of […]
Quantum algorithms bring ions to a standstill
Phys.org December 13, 2021 Most ions and other charged particles of spectroscopic interest lack the fast, cycling transitions that are necessary for direct laser cooling. In most cases, they can still be cooled sympathetically through their Coulomb interaction with a second, coolable ion species confined in the same potential. If the charge-to-mass ratios of the two ion types are too mismatched, the cooling of certain motional degrees of freedom becomes difficult. This limits both the achievable fidelity of quantum gates and the spectroscopic accuracy. Researchers in Germany developed algorithmic cooling protocol for transferring phonons from poorly to efficiently cooled modes. […]
Programmable interaction between quantum magnets
Nanowerk November 26, 2021 Using Floquet engineering researchers in Germany created a Rydberg states in an ultracold atomic gas. By applying a sequence of spin manipulations, they changed the symmetry properties of the Hamiltonian modifying the relaxation behavior of the total spin. According to the researchers engineering a wide range of Hamiltonians opens vast opportunities for implementing quantum simulation of nonequilibrium dynamics in a single experimental setting. The studies are an important step towards a better understanding of basic processes in complex quantum systems…read more. TECHNICAL ARTICLE
Molecular snakes become ladders – potential building blocks for electronics
Nanowerk November 16, 2021 It is challenging to increase the rigidity of a macromolecule while maintaining solubility. Researchers in Germany have introduced the concept of a molecular ladder. They first designed a precursor compound that contained only a single polymer chain and attached polymerizable groups – a flexible “snake.” For some of the material, the second rail of the ladder was then formed in a subsequent step by means of a zipper reaction. In addition to the polymer with a single conjugated rail, the team obtained a polymer with two conjugated rails – the stiff “ladder”. They constructed such a […]
Ultrafast magnetism: Heating magnets, freezing time
Phys.org October 18, 2021 Magnetic solids can be demagnetized quickly with a short laser pulse. However, the microscopic mechanisms of ultrafast demagnetization remain unclear. Researchers in Germany have developed a method to quantify the temperature-dependent electron–phonon scattering rate in gadolinium measuring independently the electron-phonon scattering rate for the 5d and the 4f electrons. They deduced the temperature dependence of scattering for the 5d electrons, while no effect on the phonon population is observed for the 4f electrons. The results suggest that the ultrafast magnetization dynamics in Gd is triggered by the spin-flip in the 5d electrons, found evidence of the […]