Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Observation of Topological Structures in Photonic Quantum Walks

Graciana Puentes, Ilja Gerhardt, Fabian Katzschmann, Christine Silberhorn, Jörg Wrachtrup, Maciej Lewenstein

Published Jan 1, 2014• 0 citations
Publisher

Abstract

We present an experimental observation of topological structure in 1D photonic discrete-time quantum walks. We probe the full topological landscape demonstrating emergence of localized bound states, and existence of extremely (de)localized non-Gaussian quantum states.
DOI
10.1364/cleo_qels.2014.fw1a.7

Related papers

Observation of Topological Structure in Photonic Quantum Walks

Graciana Puentes, Ilja Gerhardt, Fabian Katzschmann +3 more

We present an experimental observation of topological structure in 1D photonic discrete-time quantum walks. We probe the full topological landscape demonstrating emergence of localized bound states, and existence of extremely (de)localized non-Gaussian quantum states.

Research in Optical Sciences•Jan 1, 2014•0 citations

Observation of Topologically Protected Bound States in Photonic Quantum Walks

Takuya Kitagawa, Matthew A. Broome, Alessandro Fedrizzi +6 more

Many emerging scientific developments are rooted in topology. We investigate one-dimensional topological phases in photonic quantum walks. We observe topologically protected bound states and reveal the existence of new topological phenomena unique to driven systems.

•Jan 1, 2011•2 citations

Observation of topologically protected bound states in photonic quantum walks

Takuya Kitagawa, Matthew A. Broome, Alessandro Fedrizzi +6 more

The authors study the topological properties of such a system: a modified version of the canonical discrete-time quantum walk on a line. The authors use a previously demonstrated photonic setup to implement a split-step quantum walk, as shown in the paper. The quantum walker is encoded in the orthogonal polarization components of heralded single photons, which we created via spontaneous parametric downconversion.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•May 1, 2011•25 citations

Detecting topological invariants and revealing topological phase transitions in discrete-time photonic quantum walks

Xiaoping Wang, Lei Xiao, Xingze Qiu +3 more

We experimentally investigate topological phenomena in one-dimensional discrete-time photonic quantum walks using a combination of methods. We first detect winding numbers of the quantum walk by directly measuring the average chiral displacement, which oscillates around quantized winding numbers for finite-step quantum walks. Topological phase transitions can be identified as changes in the center of oscillation of the measured chiral displacement. The position of topological phase transition is then confirmed by measuring the moments of the walker probability distribution. Finally, we observe localized edge states at the boundary of regions with different winding numbers. We also confirm the robustness of edge states against chiral-symmetry-preserving disorder.

Physical Review A•Jul 20, 2018•43 citations

Detecting Topological Invariants in Nonunitary Discrete-Time Quantum Walks

Xiang Zhan, Lei Xiao, Zhihao Bian +5 more

We report the experimental detection of bulk topological invariants in nonunitary discrete-time quantum walks with single photons. The nonunitarity of the quantum dynamics is enforced by periodically performing partial measurements on the polarization of the walker photon, which effectively introduces loss to the dynamics. The topological invariant of the nonunitary quantum walk is manifested in the quantized average displacement of the walker, which is probed by monitoring the photon loss. We confirm the topological properties of the system by observing localized edge states at the boundary of regions with different topological invariants. We further demonstrate the robustness of both the topological properties and the measurement scheme of the topological invariants against disorder.

arXiv:1709.10287•Physical Review Letters•Sep 27, 2017•208 citations

Experimental observation of topologically protected bound states in two dimensional quantum walk

Bo Wang, Tian Chen, Xiangdong Zhang

Quantum walks (QWs) provide a powerful tool as a quantum simulator to study topological phases. However, some interesting topological phenomena in the two dimensional (2D) QW that do not exist in the one dimensional case, e.g., the edge-state-enhanced transport, have not been demonstrated experimentally. Here we have observed 2D topological bound states with vanishing Chern numbers and confirmed the robustness of these bound states with respect to perturbations and disorder, which go beyond what has been known in static systems and are unique to periodically driven systems. Our studies open up an avenue to explore topological properties in multidimensional QWs.

•Dec 18, 2019•1 citation
We experimentally investigate topological phenomena in one-dimensional discrete-time photonic quantum walks using a combination of methods. We first detect winding numbers of the quantum walk by directly measuring the average chiral displacement, which oscillates around quantized winding numbers for finite-step quantum walks. Topological phase transitions can be identified as changes in the center of oscillation of the measured chiral displacement. The position of topological phase transition is then confirmed by measuring the moments of the walker probability distribution. Finally, we observe localized edge states at the boundary of regions with different winding numbers. We also confirm the robustness of edge states against chiral-symmetry-preserving disorder.
We report the experimental detection of bulk topological invariants in nonunitary discrete-time quantum walks with single photons. The nonunitarity of the quantum dynamics is enforced by periodically performing partial measurements on the polarization of the walker photon, which effectively introduces loss to the dynamics. The topological invariant of the nonunitary quantum walk is manifested in the quantized average displacement of the walker, which is probed by monitoring the photon loss. We confirm the topological properties of the system by observing localized edge states at the boundary of regions with different topological invariants. We further demonstrate the robustness of both the topological properties and the measurement scheme of the topological invariants against disorder.
Quantum walks (QWs) provide a powerful tool as a quantum simulator to study topological phases. However, some interesting topological phenomena in the two dimensional (2D) QW that do not exist in the one dimensional case, e.g., the edge-state-enhanced transport, have not been demonstrated experimentally. Here we have observed 2D topological bound states with vanishing Chern numbers and confirmed the robustness of these bound states with respect to perturbations and disorder, which go beyond what has been known in static systems and are unique to periodically driven systems. Our studies open up an avenue to explore topological properties in multidimensional QWs.