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Charudatt Kadolkar

Publications and source records attributed to Charudatt Kadolkar.

4 recordsLinked to original sources

Large Scale AI Grading of Handwritten Physics Assessments: Score Agreement and Olympiad Team Selection Outcomes

Multimodal AI can read handwritten physics solutions, but high-stakes grading requires agreement with official scores and outcomes. This study evaluated GPT-5.5-based grading on 10364 scanned pages from 520 handwritten submissions by 416 unique candidates or students across three assessments: a national Physics Olympiad theory examination, the final Olympiad selection camp with theory and experiment components, and a university quantum-mechanics examination. Each submission was graded twice by AI using the official rubrics. The second round used revised page-by-page and evidence-location instructions developed after first-round disagreement analysis. During grading, AI did not see official human marks or AI--human comparisons. Total-score correlations with official marks were high (0.91--0.97). For the final Olympiad selection, AI recovered the same five-student team as official grading. The second round improved aggregate question-part agreement, especially where first-round disagreements were larger. The main difficulty remained exact partial-credit grading, especially in experimental work. Reliable AI grading therefore depends on detailed rubrics and should be used as a second reader or audit tool under examiner control.

physics.ed-ph↗

Regular magnetic orders in triangular and kagome lattices

We investigate the possible regular magnetic order (RMO) for the spin models with global O(3) spin rotation, based on a group theoretical approach for triangular and kagome lattices. The main reason to study these RMOs is that they are good variational candidates for the ground states of many specific models. In this work, we followed the prescription introduced by Messio et al. (L. Messio, C. Lhuillier, and G. Misguich, Phys. Rev. B, 2011, 83, 184401) for the p6m group and extended their work for different subgroups of p6m, i.e., p6, p3, p3m1, and p31m. We have listed all the possible regular magnetic orders for kagome and triangular lattices, which fall into the category of these groups. We calculate the energy and the spin structure factors for each of these states.

cond-mat.str-el↗

Q = 0 order in quantum kagome Heisenberg antiferromagnet

We have studied the nearest neighbor Heisenberg model with added Dzyaloshinskii-Moriya interaction using Schwinger boson mean field theory considering in-plane component as well as out-of-plane component. Motivated by experimental result of Vesigniete that the ground state is in Q = 0 long range order state, we first looked at the classical ground state of the model and consider the mean field ansatz which mimics the classical ground state in the large S limit. We have obtained the ground state phase diagram of this model and calculated properties of different phases. We have also studied the above model numerically using exact diagonalization up to a system size N = 30. We have compared the obtained results from these two approaches. Our results are in agreement with the experimental result of the Vesigniete.

cond-mat.str-el↗

Schwinger Boson mean field theory of kagome Heisenberg antiferromagnet with Dzyaloshinskii-Moriya interaction

We have studied the effect of the Dzyaloshinskii-Moriya interaction on kagome Heisenberg anti-ferromagnet using Schwinger boson mean field theory (SBMFT). Within SBMFT framework, Messio et al had argued that the ground state of kagome antiferromagnet is possibly a chiral topological spin liquid (Phys. Rev. Lett. 108, 207204 (2012)). Thus, we have computed zero-temperature ground state phase diagram considering the time-reversal breaking states as well as fully symmetric Ansätze. We discuss the relevance of these results in experiments and other studies. Finally, we have computed the static and dynamic spin structure factors in relevant phases.

cond-mat.str-el↗