🔬 physics

Velocity and Temperature Measurements in a Wind Tunnel using Spectrally Resolved Rayleigh and Mie Scattering

This paper demonstrates that a spectrally resolved Rayleigh and Mie scattering system, utilizing a Fabry-Perot interferometer and a scattering model to mitigate dust, condensation, and flare light interference, successfully measures velocity and temperature in a transonic wind tunnel with high accuracy, even in the presence of shock waves and naturally occurring aerosols.

Jayanta Panda, Evan D. Crowe2026-07-13
🔬 physics

A Comparative Study on the Efficiency of an SnO2/n-Si  Photodetector Using a Planar Un-scratched and a CNC Mechanically Scratched Wafer

This study demonstrates that mechanically scratching an n-Si wafer using a CNC machine to create a micro-grooved SnO2/n-Si heterojunction significantly enhances photodetector efficiency by boosting photocurrent, responsivity, and response speed through improved light trapping and reduced trap-assisted recombination, despite a trade-off in specific detectivity caused by increased dark current.

Abdullah Ali Aziz, Walla M. Mohammed2026-07-13
🔬 physics

Compliance-Induced Transition in Soft Microtubes: Near-Wall Measurements and Empirical Scaling

This study utilizes high-speed particle tracking velocimetry in soft PDMS microtubes to demonstrate that compliance-induced flow transition is characterized by a distinct near-wall localization of velocity fluctuations and lacks a universal scaling law, revealing significant inter-study heterogeneity that challenges the reliability of extrapolating stability thresholds from single assumed power laws.

Varun Gupta, Aditya Narayan Rout, M. K.S. Verma2026-07-13
🔬 physics

MHD Mixed Convection Control in an Actuated Vertically Rectangular Vented Cavity with a Rotating Core Cylinder

This study utilizes the Galerkin finite element method to demonstrate that while a strong magnetic field significantly suppresses heat transfer in a CuO-water nanofluid-filled vented cavity with a rotating core cylinder, optimizing the Reynolds number and cylinder rotation direction can substantially enhance thermal efficiency, offering valuable design insights for advanced thermal management systems.

Pushpa Akhtar, M. M. Touhid Hossain, Md. Abdul Alim, Mohammad Mokaddes Ali2026-07-13
🔬 physics

A Complex-Quaternionic Riemann–Silberstein Formalism for Single-Photon Electromagnetic Wave Packets

This paper introduces a theorem-based complex-quaternionic Riemann–Silberstein formalism that unifies the electric and magnetic components of single-photon wave packets into a single helicity-resolved biquaternionic field, thereby simplifying Maxwell's equations and clarifying the distinct operational roles of spectral localization, helicity selection, and mode matching within standard quantum electrodynamics.

Can Dogan Vurdu, Zafer Ünal2026-07-13
🔬 physics

Observation of a tripartite quantum phase for coexisting extended, localized, and critical states

This paper reports the experimental realization of a tripartite quantum phase, where extended, localized, and critical states coexist in a quasi-periodically driven orbital optical lattice, using a novel two-stage protocol to prepare, detect, and characterize their distinct transport properties with ultracold atoms.

Xiong-Jun Liu, Zhongshu Hu, Yajing Guo, Yu-Dong Wei, Bing-Chen Yao, Zhentian Qian, Xin-Chi Zhou, Bao-Zong Wang, Jianing (…)2026-07-13
🔬 physics

Gravitational-Wave Echoes from a Hayward Black Hole under Minimal Geometric Deformation

This paper demonstrates that applying a minimal geometric deformation to a regular Hayward black hole generates an exact, curvature-regular spacetime where the odd-parity gravitational-wave effective potential naturally evolves into a multi-barrier structure, creating a self-contained trapping cavity that produces gravitational-wave echoes without requiring external reflecting surfaces.

Owais Farooq Dar2026-07-13