Article
Physics, Multidisciplinary
Yonatan Sharabi, Eran Lustig, Mordechai Segev
Summary: In this study, we investigated the propagation of electromagnetic waves in disordered photonic time crystals. We observed that in spatially homogeneous media with randomly changing refractive indices, the group velocity of a pulse decreases exponentially, eventually reaching a complete stop while the intensity experiences exponential growth. These effects are greatly influenced by the Floquet band structure of the photonic time crystal, with the highest sensitivity to disorder occurring in superluminal modes. The ensemble statistics were also analyzed, showing similarities to Anderson localization with single parameter scaling.
PHYSICAL REVIEW LETTERS
(2021)
Review
Physics, Multidisciplinary
Jian Zhao, Xiaowen Hu, Stefan Gausmann, Jose Enrique Antonio-Lopez, Rodrigo Amezcua Correa, Axel Schuelzgen
Summary: Fiber-optic imaging systems have unique advantages in imaging deep into tissues, but are limited by conventional optical fiber waveguide modes and image reconstruction methods. Emerging disordered Anderson localizing optical fibers overcome these limitations and, when integrated with deep learning algorithms, offer enhanced imaging capabilities.
FRONTIERS IN PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Jiangfeng Niu, Liuge Du, Jiewen Chi, Cong Zhang, Jianwei Li, Chonglei Sun, Jia Zhao
Summary: This paper investigates the potential of disordered waveguides mediated by transverse Anderson localization for mode division multiplexing systems. The average width of localized modes is proposed as a measurement for localization length, while the design parameters of disordered waveguides have an impact on the average width of localized modes.
IEEE PHOTONICS JOURNAL
(2022)
Article
Optics
Zhun-Yong Ong
Summary: This paper proposes a theoretical model for controlling wave scattering in a two-dimensional disordered medium by analyzing the Fourier components of the disorder. By selecting appropriate wave vectors, wave scattering can be enhanced or suppressed, enabling robust coherent transmission at specific angles and wavelengths.
Article
Optics
Miri Kenig, Yoav Lahini
Summary: The application of unsupervised machine learning to the study of physical problems is an emerging field. This study uses Generative Adversarial Networks (GANs), a type of deep learning algorithm, to analyze the propagation of quantum particles on disordered chains. The results show that GANs can learn the complex quantum correlations and identify the physical control parameters in an unsupervised manner.
Article
Optics
Xiaowen Hu, Jian Zhao, Jose Enrique Antonio-Lopez, Rodrigo Amezcua Correa, Axel Schulzgen
Summary: The fusion of fiber-optic imaging with supervised deep learning has seen significant development in recent years, enabling high-quality imaging of difficult-to-reach areas. However, the requirement for paired collection of input objects and fiber outputs limits the potential of fiber-optic imaging. The use of unsupervised image reconstruction, based on transverse Anderson localization in disordered fibers, offers a new solution. In this study, unsupervised full-color imaging with cellular resolution was successfully demonstrated through a meter-long disordered fiber in both transmission and reflection modes. Two stages of unsupervised image reconstruction, involving pixel-wise standardization and fine detail recovery through a generative adversarial network, were employed. This approach allows for flexible calibration under various conditions without the need for paired images.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Optics
Jiajia Zhao, Yali Zhao, Changbang He, Jinshuai Zhang, Yiyu Mao, Wangyang Cai, Haimei Luo
Summary: This study demonstrates a method to enhance the transverse Anderson localization effect of glass-air disordered optical fiber by adjusting the number and diameter of air holes. By choosing the appropriate parameters, the localized beam radius of the fiber can be successfully reduced, even at lower air-filling fractions.
Article
Optics
Dejan Timotijevic, Jadranka M. Vasiljevic, Dragana M. Jovic Savic
Summary: We have numerically modeled two different methods for randomizing two-dimensional aperiodic photonic lattices based on Mathieu beams induced in a photorefractive media. We compared the light transport and localization in these lattices for different disorder strengths and observed disorder-enhanced light transport for all strengths of disorder. As the disorder strength increased, the light transport became diffusive-like, and further increase led to Anderson localization. This trend was more pronounced for longer propagation distances. We studied the influence of input lattice intensity on the localization effects and attributed the difference in light transport between the two randomization methods to varying levels of input lattice intensity. We observed more pronounced localization for one of the methods, and the localization lengths varied along different directions due to crystal and lattice anisotropy. We analyzed the localization effects by comparing uniform and on-site probe beam excitation positions and different probe beam widths.
Article
Optics
Sebastian Weidemann, Mark Kremer, Stefano Longhi, Alexander Szameit
Summary: Anderson's groundbreaking discovery of sudden breakdown of conductivity due to stochastic imperfections in a crystal revolutionized our understanding of disordered media and stimulated decades of studies. Recent research has shed new light on disordered media with dissipation, suggesting that dissipation can affect spectral localization and wave spreading in ways not previously observed.
Article
Mathematics, Applied
A. Ngapasare, G. Theocharis, O. Richoux, Ch. Skokos, V. Achilleos
Summary: We study the dynamical and chaotic behavior of a disordered one-dimensional elastic mechanical lattice that supports translational and rotational waves. Our results reveal rich wave-packet spreading behavior induced by coupling between translational and rotational degrees-of-freedom (DoFs) in the presence of strong disorder. Additionally, we observe energy spreading due to the coupling of DoFs in the weakly nonlinear regime, contrary to what is known for lattices with a single DoF per site. We also show that initially localized wave-packets exhibit near ballistic behavior in the presence of strong nonlinearities. Furthermore, persistent chaos is present during energy spreading, although its strength decreases over time.
Review
Physics, Multidisciplinary
Arash Mafi, John Ballato
Summary: Nearly a decade ago, researchers observed transverse Anderson localization in optical fibers, leading to the development of a new class of fibers that do not guide light based on total internal reflection. These fibers have been successfully used in endoscopic image transport and show interesting nonlinear and lasing properties.
FRONTIERS IN PHYSICS
(2021)
Article
Optics
Ricardo Roman-Ancheyta, Baris Cakmak, Roberto de J. Leon-Montiel, Armando Perez-Leija
Summary: Theoretical study shows that energy transport in a dynamically disordered photonic network can be noise-assisted, with analytically solvable solutions achievable under certain noise conditions. Non-Markovian noise types were also considered, indicating the possibility of efficient energy transport with higher dephasing rates.
Article
Physics, Multidisciplinary
Louisiane Devaud, Bernhard Rauer, Jakob Melchard, Matthias Kuehmayer, Stefan Rotter, Sylvain Gigan
Summary: The research presents a method for controlling speckle correlations behind a scattering medium through the singular value decomposition of the transmission matrix. This allows for controlling speckle grain size and shape, as well as realizing patterns with nonlocal correlations. The method also extends to volumetric speckle engineering along the axial dimension behind scattering layers.
PHYSICAL REVIEW LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Yangyu Guo, Marc Bescond, Zhongwei Zhang, Shiyun Xiong, Kazuhiko Hirakawa, Masahiro Nomura, Sebastian Volz
Summary: Anderson localization of thermal phonons has been demonstrated in graded superlattices with short-range order and long-range disorder, showing a minimum thermal conductivity with system length due to the exponential decay of transmission to a non-zero constant. Clear evidence of localization is provided through combined analysis of participation ratio, transmission, and real-space phonon number density distribution based on quantum transport simulation, which would advance heat conduction engineering by leveraging the wave nature of phonons.
Article
Optics
Jadranka M. Vasiljevi, Alessandro Zannotti, Dejan Timotijevi, Cornelia Denz, Dragana M. Jovid Savid
Summary: In this study, we introduced randomness into a complex optical system and measured its contribution to understand the relationship between randomness and complexity. The experimental results showed that increased randomness enhances light transport, with diffusive-like transport observed at lower disorder degrees and Anderson localization detected at the range of highest light transport.
