arXiv subjects

Mohit Chaudhary

Publications and source records attributed to Mohit Chaudhary.

3 recordsLinked to original sources

arXiv2026

Surface Plasmons in the Continuum

The interest to foster plasmonic applications at energies in the ultra-violet, has escalated research initiatives in clusters of unconventional plasmonic materials like aluminum and indium,for which the surface-plasmon resonance appears above the ionization potential. Naturally, the quantum mechanical description calls for the incorporation of the ionization process, thereby making the ab initio calculations challenging. We present a robust approach within the time-evolution formalism of the time-dependent density-functional theory to calculate surface plasmon resonance in the continuum of metal clusters. Using the much studied Al$_{13}^-$ as a system of reference, we show that accurate description of the continuum and of the ionization of the cluster allow to capture a broad surface-plasmon in the UV. Application of this approach in aluminum clusters has given the size-dependent evolution from discrete spectral features in Al$_{6}$ to the surface-plasmon in larger clusters in the deep ultra-violet.

physics.chem-ph↗

arXiv2025

Exploring Zero-Shot App Review Classification with ChatGPT: Challenges and Potential

App reviews are a critical source of user feedback, offering valuable insights into an app's performance, features, usability, and overall user experience. Effectively analyzing these reviews is essential for guiding app development, prioritizing feature updates, and enhancing user satisfaction. Classifying reviews into functional and non-functional requirements play a pivotal role in distinguishing feedback related to specific app features (functional requirements) from feedback concerning broader quality attributes, such as performance, usability, and reliability (non-functional requirements). Both categories are integral to informed development decisions. Traditional approaches to classifying app reviews are hindered by the need for large, domain-specific datasets, which are often costly and time-consuming to curate. This study explores the potential of zero-shot learning with ChatGPT for classifying app reviews into four categories: functional requirement, non-functional requirement, both, or neither. We evaluate ChatGPT's performance on a benchmark dataset of 1,880 manually annotated reviews from ten diverse apps spanning multiple domains. Our findings demonstrate that ChatGPT achieves a robust F1 score of 0.842 in review classification, despite certain challenges and limitations. Additionally, we examine how factors such as review readability and length impact classification accuracy and conduct a manual analysis to identify review categories more prone to misclassification.

cs.SE↗

arXiv2024

Optical spectra of silver clusters and nanoparticles of all sizes from the TDDFT+U method

The localized surface-plasmon resonances (LSPRs) of coinage-metal clusters and nanoparticles provide the basis for a great number of applications, the conception and necessary optimization of which require precise theoretical description and understanding. However, for the size range from clusters of a few atoms through nanoparticles of a few nanometers, where quantum effects and atomistic structure play a significant role, none of the methods employed to date has been able to provide high-quality spectra for all sizes. The main problem is the description of the filled shells of d electrons which influence the optical response decisively. In the present work we show that the DFT+U method, employed with real-time time-dependent density-functional theory calculations (RT-TDDFT), provides spectra in good agreement with experiment for silver clusters ranging from 4 to 923 atoms, the latter representing a nanoparticle with a diameter of 3 nm. Both the electron-hole-type discrete spectra of the smallest clusters and the broad plasmon resonances of the larger sizes are obtained. All calculations have been carried out using the same value of the effective U parameter that has been found to provide good results in bulk silver. The agreement with experiment for all sizes shows that the U parameter is surprisingly transferable. Our results open the pathway for TDDFT calculations of many practically relevant systems including clusters coupled to bio-molecules or to other nano-objects.

cond-mat.mtrl-sci↗