Advances in Topological Magic Response Enable Robust Quantum Information Storage

The quest for robust quantum information storage receives a significant boost from new research into the interplay between topology and ‘magic’ in quantum systems, a concept crucial for fault-tolerant computation. Ritu Nehra from The Abdus Salam International Centre for Theoretical Physics, Poetri Sonya Tarabunga from Technical University of Munich, and Martina Frau from the International School for Advanced Studies, alongside Mario Collura and Emanuele Tirrito, demonstrate the existence of a ‘topological magic response’, a state’s ability to maintain non-local correlations even when subjected to complex quantum operations. This research establishes that symmetry-protected topological phases consistently exhibit this response, unlike more conventional phases, and introduces a novel method using stabilizer Rényi entropies to isolate and measure this non-locally stored information. By combining analytical calculations with advanced simulations, the team reveals that this topological magic response offers a powerful new way to characterise and protect quantum information, paving the way for more resilient quantum technologies.

Topological matter provides natural platforms for robust, non-local information storage, central to quantum error correction. Researchers investigate the potential of these materials to overcome limitations in current quantum technologies, where maintaining the delicate quantum states of qubits is a significant challenge. The study focuses on understanding how topological properties can protect quantum information from environmental noise and disturbances, a key requirement for building practical quantum computers. Specifically, the team explores the creation and manipulation of exotic quasiparticles within topological materials, leveraging their inherent stability for encoding and processing quantum data. This approach aims to develop more resilient and scalable quantum systems, paving the way for advancements in computation, communication, and sensing technologies.

Topological Rényi Entropy Calculations for Critical States

Scientists have developed a detailed method for calculating topological Rényi entropy, a measure of entanglement in quantum systems, for various quantum states. This work explores how this entropy reveals the underlying structure of entanglement, particularly its robustness to local disturbances. The method utilizes the stabilizer formalism, a powerful technique for analyzing many-body entanglement, and considers different ways to divide the quantum system into parts to quantify the entanglement between them. The research examines fundamental states like the Greenberger-Horne-Zeilinger (GHZ) state and cluster state, as well as the tri-critical Ising model, to test and refine the calculations.

By calculating the topological Rényi entropy for different quantum states and partitions, scientists can understand how entanglement is distributed within the system. Results demonstrate that the GHZ state exhibits zero entropy across all divisions, indicating a lack of robustness to local disturbances, while the cluster state maintains a consistent entropy, demonstrating its robustness. The tri-critical Ising model exhibits entropy values consistent with the Ising and cluster Ising models. This work provides a framework for calculating entanglement in other quantum states and systems, with implications for quantum information and condensed matter physics.

Topological Magic Response Reveals Robust Quantum Phases

Scientists have achieved a breakthrough in understanding how to quantify and harness non-local correlations within topological phases of matter, crucial for robust quantum information storage and error correction. This work introduces the concept of “topological magic response,” which describes a state’s ability to spread across stabilizer space when subjected to specific quantum operations, revealing the presence of non-local correlations. Unlike traditional measures, this response function probes how a phase reacts to perturbations, distinguishing between phases that support robust quantum information and those that do not. The team developed a novel method utilizing stabilizer Rényi entropies to isolate non-locally stored information.

Through a combination of exact analytic computations and large-scale simulations, researchers demonstrated that symmetry-protected topological (SPT) phases consistently exhibit this topological magic response, while both symmetry-broken and paramagnetic phases do not. Results demonstrate that trivial phases exhibit only local, additive magic, whereas SPT phases robustly support non-local topological magic. The magic response of SPT ground states closely parallels topological entanglement entropy, identifying these phases as natural hosts of intrinsically non-local magic resources. This research establishes that magic, like entanglement, can display universal non-local features, but is a strictly stronger resource, with implications for fault-tolerant quantum computing architectures. Measurements confirm that the defined topological stabilizer Rényi entropy allows efficient computation even for large systems, offering a powerful tool for characterizing and harnessing non-local correlations in topological phases.

Topological Magic Response Identifies Robust Phases

Scientists demonstrate that symmetry-protected topological phases exhibit a “topological magic response,” indicating their ability to maintain non-local correlations even under specific types of computational perturbations, while simpler phases do not. This topological magic response is measured using a combination of stabilizer Rényi entropies, which effectively isolate information stored non-locally within the system. The team investigated this phenomenon within the tri-critical Ising model, confirming that the topological stabilizer Rényi entropy accurately distinguishes between topological and trivial phases across the entire phase diagram. These findings provide a new tool for characterizing topological phases and understanding their resilience to computational errors.