SSCU Student Seminar
Name: Mr. Kaustav Chatterjee
Title: Probing topology of 2D topological insulators through quantum computing.
Date & Time: Thursday, 29th January 2026 at 4.00 p.m.
Venue: Rajarshi Bhattacharyya Memorial Lecture Hall, Chemical Sciences Building
Abstract:
Quantum computing offers a potential pathway for simulating phases of matter that are computationally intractable for classical devices, particularly in the regime of strongly correlated systems. However, before these advanced simulations can be realized, it is essential to establish and validate robust quantum algorithms on well-understood non-interacting testbeds. In condensed matter physics, the characterization of topological phases is governed by invariants such as the Chern number, which traditionally requires integration of the Berry curvature over the Brillouin zone.
In this talk, I will discuss how hardware-efficient quantum circuits provide an alternative approach for extracting these invariants by directly simulating the adiabatic evolution of the quantum state. The proposed architecture integrates a discretized adiabatic path with a Hadamard-test readout, allowing the network to learn the local Berry flux directly from the qubit interference. By mapping two-band Hamiltonians to single-qubit rotations, the requirement for expensive entangling gates is minimized . The results, obtained from the 5-qubit “Helmi” superconducting processor, demonstrate superior stability against hardware noise and excellent agreement with exact theoretical predictions for the Qi-Wu-Zhang and Haldane models. This approach provides physically consistent predictions for topological invariants, suggesting a promising alternative to classical solvers for characterizing topological quantum matter.
References:
[1] Niedermeier, Marcel, et al. “Quantum computing topological invariants of two-dimensional quantum matter.” Physical Review Research 6.4 (2024): 043288.
[2] Murta, Bruno, Gonçalo Catarina, and Joaquín Fernández-Rossier. “Berry phase estimation in gate-based adiabatic quantum simulation.” Physical Review A 101.2 (2020): 020302.
[3] Lahtinen, Ville, and Jiannis Pachos. “A short introduction to topological quantum computation.” SciPost Physics 3.3 (2017): 021.
[4] Fukui, Takahiro, Yasuhiro Hatsugai, and Hiroshi Suzuki. “Chern numbers in discretized Brillouin zone: Efficient method of computing (spin) Hall conductances.” Journal of the Physical Society of Japan 74.6 (2005): 1674-1677.
[5]Hastings, Matthew B., and Spyridon Michalakis. “Quantization of Hall conductance for interacting electrons on a torus.” Communications in Mathematical Physics 334.1 (2015): 433-471.