arXiv subjects

Ya-Ru Wang

Publications and source records attributed to Ya-Ru Wang.

6 recordsLinked to original sources

arXiv2026

CP violations in neutrino oscillations modulated by singular and non-singular gravities

Flavor oscillations in curved space-time provide a novel channel to explore the unknown parameters of neutrinos. In this work, the gravity-modulated CP violations (CPVs) in neutrino oscillations were investigated under the Reissner-Nordstrom, Hayward, and Simpson-Visser metric. The interplay among the CPV, the properties of neutrinos, and the space-time is illustrated with analytical and numerical methods. The morphologies of the flavor-oscillation curves show that the information on the mass-ordering, the absolute mass, and the gravitational parameters could be encoded into the amplitudes and periods of the CPVs. Hence, the characteristic of the space-time background may be identified through its modulation effects on the CPV, such as amplification, damping on the amplitudes.

hep-ph↗

arXiv2025

Relating the dynamics of photo de-mixing in mixed bromide-iodide perovskites to ionic and electronic transport

The observation of reversible de-mixing phenomena in mixed-halide perovskites under illumination is one of the most challenging as well as intriguing aspects of this class of materials. On the one hand, it poses critical constraints to the compositional space that allows reliable design of absorbers for perovskite photovoltaics. On the other hand, it holds potential for the development of novel optoionic devices where an ionic response is triggered via optical stimuli. Funda-mental questions about the origin of such photo de-mixing process remain unanswered, both in terms of its mechanism as well as thermodynamic description. Here, we relate in-situ measurements of ionic and electronic transport of mixed bromide-iodide perovskite thin films performed during photo de-mixing with the evolution of their optical and morpho-logical properties. The results point to the definition of different stages of the de-mixing process which, based on micros-copy and spectroscopic measurements, we assign to regimes of spinodal decomposition and nucleation of quasi-equilibrium iodide- and bromide-rich phases. Combined with density functional theory calculations, we explore the role of dimensionality in the mechanism and reversibility of photo de-mixing and dark re-mixing processes, referring to elec-tronic and ionic contributions to the de-mixing driving force. Additionally, our data emphasizes the role of the surface, as significantly different de-mixing dynamics, in terms of extent and reversibility, are observed for films with or without encapsulation. Our comprehensive analysis of transport, phase and optical properties of mixed-halide perovskites pro-vides guidelines for future materials design as well as for the more general fundamental understanding of light-induced ionic phenomena.

cond-mat.mtrl-sci↗

arXiv2025

Effects of gravitational lensing on neutrino oscillation in Hu-Sawicki f(R) gravity

Gravitational lensing serves as a powerful probe of compact astrophysical objects and dark matter distributions. As relativistic counterparts to photons, neutrinos experiencing lensing offer a complementary means to investigate the properties of curved spacetimes. This paper studies neutrino oscillations within the spacetime geometry described by the Hu-Sawicki f(R) gravity model, focusing on the modifications induced by gravitational lensing. We calculate the oscillation phases for both radial and non-radial neutrino propagation and derive the corresponding flavor transition probabilities for 2-flavor and 3-flavor scenarios under the weak-field approximation. Our analysis demonstrates that the lensing-affected oscillation probabilities exhibit a clear dependence on the Hu-Sawicki model parameter $\lambda$ , the neutrino mass hierarchy, and the absolute value of the lightest neutrino mass. Furthermore, extending the analysis beyond the weak-field regime reveals that strong-field gravitational lensing amplifies these effects. These results, while theoretical, indicate that future high-precision measurements of lensed neutrinos from compact astrophysical objects could, in principle, help test modified gravity models and constrain neutrino parameters, provided that experimental and wave-packet decoherence challenges are overcome.

hep-ph↗

arXiv2024

Influences of non-standard interactions on PeV neutrino events with and without a $L_{\alpha}-L_{\beta}$ symmetry

The recently reported astrophysical neutrinos events in the TeV-PeV energy range open a winder to explore new physics at energy frontiers. In this paper, we examine effects of non-standard interactions (NSIs) on the PeV neutrinos events. We consider NSIs with and without a gauge symmetry $L_{\alpha}$ - $L_{\beta}$. We find that, for typical $\mu^{\pm}$ damping and $\pi^{\pm}$ decay sources, the NSI with an extra gauge symmetry has more noticeable effects on the PeV events. Therefore, the detection of the events in the upcoming experiments could set stringent constraints on the NSI parameters in the $L_{\alpha}$ - $L_{\beta}$ symmetric case.

hep-ph↗

arXiv2021

Photo de-mixing in Dion-Jacobson two-dimensional mixed halide perovskites

Two-dimensional (2D) halide perovskites feature a versatile structure, which not only enables the fine-tuning of their optoelectronic properties but also makes them appealing as model systems to investigate the fundamental properties of hybrid perovskites. In this study, we analyzed the changes in the optical absorption of 2D Dion-Jacobson mixed halide perovskite thin films (encapsulated) based on (PDMA)Pb(I0.5Br0.5)4 (PDMA: 1,4-phenylenedimethanammonium spacer) exposed to a constant illumination. We demonstrate that these 2D mixed-halide perovskites undergo photo de-mixing with direct transformation from the pristine phase to the de-mixed phases. Almost complete re-mixing of these phases occurs when the sample is left in the dark, showing that the process is reversible in terms of optical properties. On the other hand, exposure to light appears to induce structural changes in the thin film that are not reversible in the dark. We have further investigated temperature-dependent absorption measurements under light to extract the photo de-mixed compositions and to map the photo-miscibility-gap. This work thereby reveals that photo de-mixing occurs in Dion-Jacobson two-dimensional hybrid perovskites and provides strategies to address the role of light in the thermodynamic properties of these materials.

physics.chem-ph↗

arXiv2021

Weak Decays of Doubly Heavy Baryons: ${\cal B}_{cc}\to {\cal B} D^{(*)}$

The discovery of $Ξ_{cc}^{++}$ has inspired new interest in studying doubly heavy baryons. In this study, the weak decays of a doubly charmed baryon ${\cal B}_{cc}$ to a light baryon ${\cal B}$ and a charm meson $D^{(*)}$ (either a pseudoscalar or a vector one) are calculated. Following our previous work, we calculate the short distance contributions under the factorization hypothesis, whereas the long distance contributions are modeled as the final state interactions which are calculated with the one particle exchange model. We find that the ${\cal B}_{cc}\to {\cal B} D^{*}$ decays' branching ratios are obviously larger, as they receive contributions of more polarization states. Among the decays that we investigate, the following have the largest branching fractions: ${\cal BR}(Ξ_{cc}^{++}\rightarrowΣ^{+}D^{*+}) \in [0.46\%, 3.33\%]$ estimated with $τ_{Ξ_{cc}^{++}}=256$ fs; ${\cal BR}(Ξ_{cc}^{+}\rightarrowΛD^{*+}) \in [0.38\%, 2.63\%]$ and ${\cal BR}(Ξ_{cc}^{+}\rightarrowΣ^{0} D^{*+}) \in [0.45\%, 3.16\%]$ with $τ_{Ξ_{cc}^+}=45$ fs; and ${\cal BR}(Ω_{cc}^{+}\rightarrowΞ^{0} D^{*+}) \in [0.27\%, 1.03\%]$, ${\cal BR}(Ω_{cc}^{+}\rightarrowΞ^{0} D^{+}) \in [0.07\%, 0.44\%]$ and ${\cal BR}(Ω_{cc}^{+}\rightarrowΣ^{0} D^{*+}) \in [0.06\%, 0.45\%]$ with $τ_{Ω_{cc}^+}=75$ fs. By comparing the decay widths of pure color commensurate channels with those of pure bow-tie ones, we find that the bow-tie mechanism plays an important role in charm decays.

hep-ph↗