Comets’ brightness

Brightening is due to a combination of observing geometry, as the comet approaches both the Sun and the Earth, and increasing back-scattering cross-section.Total Magnitude(brightness) of comet: M1 absolute magnitude of the comet (a baseline brightness value).Δ: geocentric distance (distance between...

Meteoroid in earth atmosphere:

Fragmentation, rather than ablation, is the dominant mechanism of mass loss. Here Rayleigh–Taylor (Hydrodynamic )instability occurs at the interface between two fluids of different densities, lighter fluid is pushing the heavier fluid.Meteoroid Trajectory equation:Cd is the drag coefficient of meteoroid,...

Babinet's Principle for non linear optics

Babinet’s principle states that if you have an opaque object and its complementary aperture, they should produce identical diffraction patterns when light passes through them. Ex. A thin metal rod blocking light should create the same diffraction pattern as a slit of the same shape cut into a metal sheet.Babinet’s principle does not hold for nonlinear optics.super-resolution effect:In linear optics,...

Study of birefringence in shear thinning fluid

Birefringence is an optical property of materials where light splits into two different rays, each traveling at a different speed and direction when passing through the material.Phase retardation (∆) refers to the difference in the phase of light waves as they pass through a birefringent material (like...

Symmetry change in Magnetite

Below the Verwey transition temperature (~110K in this experiment), Magnetite Fe3O4 structure distorts into a monoclinic shape, where one of the angles slightly deviates from 90° (β ≈ 90.23°). This distortion introduces a shear strain. The change is accompanied by charge ordering of the Fe2+ and Fe3+ ions to form “trimerons”, valence-ordered Fe3+-Fe2+-Fe3+ linear structures, which confine the...

two superconducting gaps observed for CsV₃Sb₅

The two superconducting gaps have been observed for CsV₃Sb₅ material. A charge density wave (CDW) is a state where the electron density in a material forms a periodic pattern instead of being uniform. This happens because of electron-phonon interactions, where electrons couple with vibrations in the crystal lattice.As per CDW in CsV₃Sb₅, electron density and lattice distortions repeat every two...

Chromium based tantalum disulfide properties

Study was done on Cr₁/₃TaS₂ (Cr atoms are inserted into a layered compound TaS₂ (tantalum disulfide)). The Raman Scattering method was used here.Pressure changes bond lengths and angles and, at the same time, systematically reduces the van der Waals distance and modifies the structural c/a ratio.Cr₁/₃TaS₂ has a smaller van der Waals gap, making it less change to structural distortions than Fe based...

Study of Cesium lead bromide- local polarization

Material CsPbBr₃ (cesium lead bromide) was studied here. It is widely used in solar cells, LEDs.At high temperatures (>100K), transport shifts to a band-like motion, where charge carriers move smoothly.At low temperatures (<100K), charge carriers move by hopping transport (jumping between localized...

Study of Isotropic superconductivity of Nickelate La4Ni3O10

Nickelate La4Ni3O10-δ was studied here at pressure 50.2 GPa and a magnetic field up to 34T for both out-of-plane (H⊥ab) and in-plane (H//ab) direction.The upper critical magnetic field(𝝁𝟎𝑯𝐜𝟐 ) of La4Ni3O10-δ is nearly isotropic, with the anisotropic parameter γ monotonically decrease from 1.4 near Tc to 1 at lower temperatures.By analyzing the upper critical magnetic field using the two-band...

Key Points of article related to Sn-based perovskite solar cells

 (The electron barrier is an energy barrier that prevents or slows down the movement of electrons across an interface between two materials. It occurs due to a difference in energy levels when two materials come into contact.Different materials have different Fermi levels. To balance out, electrons move from the higher-energy side to the lower-energy side. This movement bends the bands and creates...
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