Adrok Ltd.’s Post

Spectroscopy is a technique used to analyse the interaction between matter and electromagnetic radiation. It allows scientists to determine the composition, structure, and physical properties of matter by examining how it absorbs, emits, or scatters light. Electromagnetic Spectroscopy involves the use of electromagnetic radiation, which includes a wide range of wavelengths from gamma rays to radio waves. Different types of spectroscopy focus on different parts of this spectrum. Here are some of Adrok Ltd. results from non-invasively scanning rocks using one of our laboratory systems, at the famous Royal Ontario Museum in Toronto, showed sulphides can be separated from silicates using energy measurements derived from FFT at statistically significant levels. #innovation #research #geosciences #spectroscopy #electromagnetics

📃Scientific paper: The cause of the difference in the propagation distances between compact and transient jets in black-hole X-ray binaries Abstract: Accreting black-hole binaries change their properties during evolution, passing through two main luminous states, dominated by either hard or soft X-rays. In the hard state, steady compact jets emitting multiwavelength radiation are present. Those jets are usually observed in radio, and when resolved, their extent is $\lesssim\! 10^\{15\}$ cm. Then, during hard-to-soft transitions, powerful ejecta in the form of blobs appear. They are observed up to distances of $\sim\! 10^\{18\}$ cm, which are $\gtrsim$1000 times larger than the extent of hard-state jets. On the other hand, estimates of the accretion rates during most luminous hard states and the hard-to-soft transitions are very similar, implying that maximum achievable powers of both types of jets are similar and cannot cause the huge difference in their propagation. Instead, we explain the difference in the propagation length by postulating that the ejecta consist of electron-ion plasmas, whereas the hard-state jets consist mostly of electron-positron pairs. The inertia of the ejecta are then much higher than those of compact jets, and the former are not readily stopped by ambient media. A related result is that the accretion flow during the hard state is of Standard and Normal Evolution \(SANE\), while it is a Magnetically Arrested Disk \(MAD\) during transient ejections. The pairs in hard-state jets can be produced by collisions of photons of the hard spectrum emitted by hot accretion flows within the jet base. On... Continued on ES/IODE ➡️ https://etcse.fr/uIofJ ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

I am pleased to announce that our article on "Coupled circularly polarized electromagnetic soliton states in magnetized plasmas", the research outcome of a great collaboration, has been just published in Nonlinear Dynamics. The article is now accessible online (Open Access) in: https://lnkd.in/dYSTHtgf   In the article, the interaction between two co-propagating electromagnetic pulses in a magnetized plasma is considered using a fluid-Maxwell model. Systematic analysis reveals the existence of three different types of vector soliton modes. An exhaustive parametric investigation in terms of frequency bands and in a wide range of magnetic field strengths leads to results that may be applicable in beam-plasma interaction scenarios as well as in space plasmas.

In our recently published work in Scientific Reports, we have a proposed an analytical model to study graphene-based spatiotemporally modulated structures working at THz frequencies. Spatiotemporally modulated structures with periodic variations in one or more of their electromagnetic properties in both time and space exhibit interesting behaviours such as nonreciprocal response, asymmetric band gap in the dispersion diagram, frequency mixing, and mode conversion. These unique features make them a great candidate for development of integrated THz devices such as mixers, modulators, antennas, isolators, mode convertors, and circulators. https://lnkd.in/dbVzWznz

𝐏𝐡𝐲𝐬𝐢𝐜𝐢𝐬𝐭𝐬 𝐞𝐦𝐩𝐥𝐨𝐲 𝐢𝐨𝐧 𝐦𝐢𝐜𝐫𝐨𝐬𝐜𝐨𝐩𝐞 𝐭𝐨 𝐨𝐛𝐬𝐞𝐫𝐯𝐞 𝐮𝐧𝐮𝐬𝐮𝐚𝐥 𝐜𝐨𝐥𝐥𝐢𝐬𝐢𝐨𝐧𝐬 𝐢𝐧 𝐬𝐥𝐨𝐰-𝐦𝐨𝐭𝐢𝐨𝐧 With the help of a novel ion microscope experiment, researchers at the Universität Stuttgart and Universität Hamburg observed and understood the collisional behavior between highly excited and charged particles inside an ultracold gas. They report on their experiment and theory collaboration, which is important for understanding fundamental processes in nature, in the journal Physical Review Lets. 𝐑𝐞𝐚𝐝 𝐦𝐨𝐫𝐞  https://lnkd.in/eM5VvpjY 𝐎𝐫𝐢𝐠𝐢𝐧𝐚𝐥 𝐩𝐮𝐛𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧 M. Berngruber, Daniel Bosworth, O.A. Herrera-Sancho, V. Anasuri, N. Zuber, F. Hummel Frederic H., J. Krauter, F. Meinert, R. Löw, Peter Schmelcher and T. Pfau In Situ Observation of Non-Polar to Strongly Polar Atom-Ion Collision Dynamics Physical Review Letters 133, 083001 (2024) DOI: 10.1103/PhysRevLett.133.083001 Physical Review #ionmicroscope #rydbergatoms

In this review, researchers first introduce the basic concepts of plasmonic modes in nanoparticle-on-mirror (NPoM) structures. Interactions between plasmons and quasi-particles in 2D materials, e.g., excitons and phonons, from weak to strong coupling and potential applications are described in detail. Related phenomena in subnanometer metallic gaps separated by 2D materials, such as quantum tunneling, is also discussed. View original article https://lnkd.in/gi95EvFc Control of light–matter interactions in two-dimensional materials with nanoparticle-on-mirror structures

📃Scientific paper: Gravitational waves from axion domain walls in double level crossings Abstract: We investigate the nano-Hertz gravitational waves emitted by axion domain walls annihilation from the double level crossings. The double level crossings exists in the mass mixing between two axion fields, one of which is the $Z\_\{\mathcal N\}$ QCD axion. Here we consider a general mixing case that the heavy and light mass eigenvalues do not necessarily have to coincide with the axion masses. In order to form the domain walls, the axions should start to oscillate slightly before the first level crossing, and the initial oscillation energy density should be large to climb over the barrier of potential. In this case, the axion dynamics has a chaotic run-away behavior, which is considered to be accompanied by domain walls formation. Then we investigate the gravitational waves emitted by axion domain walls annihilation, which is determined by their peak frequency and peak amplitude. Finally, we show the predicted nano-Hertz gravitational waves spectra from the double level crossings, which can be tested by the current and future pulsar timing array projects. ;Comment: 6 pages, 2 figures Continued on ES/IODE ➡️ https://etcse.fr/9u2TK ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

Researchers from the University of Bonn and RPTU created a one-dimensional photon gas by confining and cooling light particles in a narrow space. They achieved this by using microscopically small gutters inside a container filled with a dye solution, stimulated by a laser. By tweaking the reflective surfaces, they discovered new behaviors in photon gases. These gases showed different phase transition behaviors due to increased thermal fluctuations in one dimension, providing insights into quantum optical effects. #QuantumState #PhotonGas #QuantumPhysics https://lnkd.in/gM2Niejb

📚 Exciting News! 🎉 I am thrilled to announce that my latest research article has been published in the Nature Scientific Reports Journal ! 🌐🔬 Title: “Optimizing an electromagnetic wave absorber for bi-anisotropic metasurfaces based on toroidal modes” In our recent study, we tackled the design and optimization of an electromagnetic wave absorber for far-field wireless power transmission (WPT). Our goal? To efficiently absorb energy from ambient RF electromagnetic waves without relying on a ground plane. How did we achieve this? By employing metasurfaces with chiral components. 🔍 Key Findings: 1.   #Metasurface : We integrated trioidal moments into our design theory, resulting in a metasurface that operates across two frequency bands and produces high-quality resonance. 2.   #Bianisotropic: Our exploration delved into the intriguing property of structures with dual non-homogeneity. 3.   #Polarization Insights: We analyzed polarization tensor coefficients and studied the electromagnetic response of non-homogeneous metasurfaces. 4.   #Chiral Metasurfaces: We introduced the concept of electromagnetic chirality, exploring its implications for polarization properties. hosein allahverdizade, Sina Aghdasinia, behrouz ahmadpour, Mohammad Bemani For more details please cheack : https://lnkd.in/dUNHN5PX

I would like to share my freshly published work on topological insulator materials in Surface Science journal. I have used scanning tunneling microscopy (which sees individual atoms) to characterize gold nano-islands on the surface of such materials. My very local, atomic-scale results are combined with macro-scale SOLARIS (Krakow, Poland) synchrotron experiments - the X-ray absorption spectroscopy. https://lnkd.in/eKPYwuHC "The in-plane band bending effect around Au islands grown on the Bi2Te3 topological insulator" For advertisement 🙂 , here is my own STM image of the surface of such materials. You can see the atomic rows and some light areas - surface atoms affected by defects below the surface. They have slightly different characteristics and therefore appear differently. There is also dark area - the absence of one atom.