Phys.org January 25, 2021 Nonlinear optical techniques have made it possible to change the color of light and modify its spectral bandwidth without compromising the intensity. However, nonlinear optical techniques are not readily available in the XUV region of the electromagnetic spectrum. Researchers in Germany have demonstrated a concept for efficient spectral compression by four-wave mixing exploiting a phase-matching scheme based on closely spaced resonances. They compressed broadband radiation in the 145–130 nm wavelength range into a narrow-bandwidth XUV pulse at 100.3 nm wavelength in the presence of a broadband near-infrared pulse in a krypton gas jet. The narrowband XUV pulses has […]
Tag Archives: S&T Germany
Neither liquid nor solid
Science Daily January 5, 2021 Most experiments involving colloidal suspensions have relied on spherical colloids. Using polymer chemistry researchers in Germany manufactured small plastic particles, stretching, and cooling them until they achieved their ellipsoid forms and then placed them in a suitable solvent. They found that due to their distinct shapes their particles had orientation which gave rise to entirely new and previously unstudied kinds of complex behaviours. By changing particle concentrations in the suspensions, and tracking both the translational and rotational motion of the particles using confocal microscopy, they observed two competing glass transitions — a regular phase transformation […]
Artificial intelligence solves Schrödinger’s equation
Phys.org December 21, 2020 The goal of quantum chemistry is to predict chemical and physical properties of molecules based solely on the arrangement of their atoms in space, avoiding the need for resource-intensive and time-consuming laboratory experiments. In principle, this can be achieved by solving the Schrödinger equation. Up to now, it has been impossible to find an exact solution for arbitrary molecules that can be efficiently computed. To solve this problem researchers in Germany have proposed PauliNet, a deep-learning wavefunction ansatz that achieves nearly exact solutions of the electronic Schrödinger equation for molecules with up to 30 electrons. PauliNet […]
Detecting bacteria with fluorescent nanosensors
Nanowerk November 25, 2020 Researchers in Germany developed a set of near infrared fluorescent nanosensors are based on single-walled carbon nanotubes that fluoresce in the NIR optical tissue transparency window which offers ultra-low background and high tissue penetration. They are chemically tailored to detect released metabolites as well as specific virulence factors and integrated into functional hydrogel arrays with 9 different sensors. These hydrogels are exposed to clinical isolates of 6 important bacteria and remote (≥25 cm) NIR imaging allows to identify and distinguish bacteria. Sensors are also spectrally encoded to differentiate the two major pathogens P. aeruginosa as well as […]
German Sachsen Frigate to Test a New Naval Laser Weapon
Defense Update November 26, 2020 The laser source demonstrator can be employed in various projects to study military applications of high-power laser. The first project of the new laser will be a trial phase onboard the F219 Sachsen Class – the lead ship of this class. It consists of twelve nearly identical 2kW fiber laser modules with close to diffraction-limited beam quality. A beam combiner – a subassembly that turns multiple beams into a single beam through dielectric grid technology – couples the twelve fiber-laser beams to form a single laser beam with excellent beam quality. Spectral coupling technology offers […]
Physicists develop efficient modem for a future quantum internet
Phys.org November 5, 2020 A central research object is the interface between local quantum devices and light quanta that enable the remote transmission of highly sensitive quantum information. Researchers in Germany integrated a thin crystal of erbium-doped yttrium orthosilicate a cryogenic Fabry-Perot resonator leading to 56-fold enhancement of the emission rate with an out-coupling efficiency of 46%. They demonstrated that the emitter properties are not degraded. They observed ensemble-averaged optical coherence up to 0.54 ms, which exceeds the 0.19 ms lifetime of dopants at the cavity field maximum. The approach is also applicable to other solid-state quantum emitters, such as […]
A milestone in quantum physics: Physicists successfully carry out the controlled transport of stored light
Nanowerk October 13, 2020 Quantum memories for light, realized with cold atomic samples as the storage medium, are prominent for their high storage efficiencies and lifetime. Researchers in Germany used ultra-cold rubidium-87 atoms as a storage medium for the light as to achieve a high level of storage efficiency and a long lifetime. They transported the stored light over 1.2 mm. They showed that the transport process and its dynamics only have a minor effect on the coherence of the storage. Extending the presented concept to longer transport distances and augmenting the number of storage sections will allow for the […]
Bacteria fed on a customized diet produce biodegradable polymers for alternative packaging in the cosmetics industry
Fraunhofer Research October 1, 2020 To create biologically based, biodegradable polymers as a replacement for plastic packaging in the cosmetics industry researchers in Germany are cultivating bacteria fed on a variety of waste materials, ranging from wood waste and oil and sugar residues to glycerol from biodiesel production. They cause the bacteria to produce specific intracellular storage granules, polyhydroxyalkanoates (PHAs). The PHA is sent in the form of a white powder is turned into granules and then into a polymer film. Initial testing on small sheets of the polymer material for characteristics such as thermal stability, plasticity, and various barrier […]
Rapid rescue of buried people
Fraunhofer Research October 1, 2020 Researchers in Germany have developed a mobile radar device that can search hectare-sized areas quickly and thoroughly. The new technology combines greater mobility with accurate detection of vital signs. They have developed an algorithm designed to detect irregular heartbeats. The system detects vital signs close to the stationary radar system, successfully putting it to the test at distances of up to 15 meters. In about two years they expect to transition the technology to UAV based applications to reliably detect buried casualties…read more.
Physicists develop printable organic transistors
Nanowerk September 22, 2020 Conventional horizontal organic thin-film transistors are very slow due to the hopping-transport in organic semiconductors, so they cannot be used for applications requiring high frequencies. Researchers in Germany have developed powerful vertical organic transistors with two independent control electrodes characterized by a high switching frequency and an adjustable threshold voltage. With these developments even single transistors can be used to represent different logical states (AND, NOT, NAND). Furthermore, the adjustable threshold voltage ensures signal integrity and low power consumption. In the future, these transistors could make it possible to realize even sophisticated electronic functions such as […]