{"title":"Progress on artificial flat band systems: classifying, perturbing, applying","authors":"C. Danieli, S. Flach","doi":"10.1080/00018732.2026.2658992","DOIUrl":"https://doi.org/10.1080/00018732.2026.2658992","url":null,"abstract":"We highlight recent progress in the study of artificial flat band systems with a threefold focus. First, we discuss single-particle flat band physics, which has advanced through the design of various flat band generators. These generators rely on the classification of flat bands in terms of compact localized states – their fundamental building blocks. A related development is the complete real-space description of flat band projectors. Next, we review studies on perturbations of flat bands, which provide new insights into the effects of disorder and, more importantly, the intricate interplay between many-body interactions and flat band physics. Finally, we survey the growing number of experimental realizations of flat bands across diverse physical platforms.","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147735884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Parity-time symmetry with coherent atomic gases: a concise review on recent progress","authors":"Chao Hang, Guoxiang Huang","doi":"10.1080/00018732.2025.2610595","DOIUrl":"https://doi.org/10.1080/00018732.2025.2610595","url":null,"abstract":"","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146005771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yves H. Kwan, Ziwei Wang, Glenn Wagner, Nick Bultinck, Steven H. Simon, Siddharth A. Parameswaran
{"title":"Mean-field modeling of moiré materials: a user's guide with selected applications to twisted bilayer graphene","authors":"Yves H. Kwan, Ziwei Wang, Glenn Wagner, Nick Bultinck, Steven H. Simon, Siddharth A. Parameswaran","doi":"10.1080/00018732.2025.2600658","DOIUrl":"https://doi.org/10.1080/00018732.2025.2600658","url":null,"abstract":"We review the theoretical modeling of moiré materials, focusing on various aspects of magic-angle twisted bilayer graphene (MA-TBG) viewed through the lens of Hartree–Fock mean-field theory. We first provide an elementary introduction to the continuum modeling of moiré bandstructures, and explain how interactions are incorporated to study correlated states. We then discuss how to implement mean-field simulations of ground state structure and collective excitations in this setting. With this background established, we rationalize the power of mean-field approximations in MA-TBG, by discussing the idealized ‘chiral-flat’ strong-coupling limit, in which ground states at electron densities commensurate with the moiré superlattice are <i>exactly</i> captured by mean-field <i>ansätze</i>. We then illustrate the phenomenological shortcomings of this limit, leading us naturally into a discussion of the intermediate-coupling incommensurate Kekulé spiral (IKS) order and its origins in ever-present heterostrain. IKS and its placement within an expanded Hartree–Fock manifold form our first ‘case study’. Our second case study involves time-dependence, and focuses on the collective modes of various broken-symmetry insulators in MA-TBG. As a third and final case study, we return to the strong-coupling picture, which can be stabilized by aligning MA-TBG to an hBN substrate. In this limit, we show how mean field theory can be adapted to the translationally non-invariant setting in order to quantitatively study the energetics of domain walls in orbital Chern insulating states. We close with a discussion of extensions and further applications. Used either as a standalone reference or alongside the accompanying open-source code, this review should enable readers with a basic knowledge of band theory and many-body physics to systematically build and analyze detailed models of generic moiré systems.","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145801172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Solid-state high-order harmonic generation: emerging frontiers in ultrafast and quantum light science","authors":"M. F. Ciappina","doi":"10.1080/00018732.2025.2598130","DOIUrl":"https://doi.org/10.1080/00018732.2025.2598130","url":null,"abstract":"","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145680051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new dawn for Advances in Physics","authors":"Paolo Radaelli, Nigel Balmforth","doi":"10.1080/00018732.2025.2580807","DOIUrl":"https://doi.org/10.1080/00018732.2025.2580807","url":null,"abstract":"","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"135 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145645161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multidimensional soliton systems: an update","authors":"Boris Malomed","doi":"10.1080/00018732.2025.2586343","DOIUrl":"https://doi.org/10.1080/00018732.2025.2586343","url":null,"abstract":"A briefly formulated update of the recently published review [B.A. Malomed, <i>Multidimensional soliton systems</i>. Adv. Phys. 9(1) (2024), pp. 2301592] on the topic of multidimensional solitons (chiefly, in nonlinear optics and atomic Bose–Einstein condensates (BECs)) is presented. The update briefly summarizes some notable results on this topic that have been reported very recently, and offers a compact outline of the directions of the current experiment and theoretical work in this and related fields. In particular, as concerns newest experimental findings, included are the creation of multiple <i>quantum droplets</i> in prolate BEC, and the observation of expanding toroidal light structures in linear optics. The update of theoretical results includes the analysis of 2D solitons in the optical system with the quadratic nonlinearity and <i>fractional diffraction</i>, and the prediction of stable 3D <i>vortex solitons</i> in various BEC schemes with long-range interactions.","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145536098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Introduction to Langevin stochastic processes","authors":"Leticia F. Cugliandolo","doi":"10.1080/00018732.2025.2580840","DOIUrl":"https://doi.org/10.1080/00018732.2025.2580840","url":null,"abstract":"","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145455167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lectures on quantum supreme matter","authors":"Jan Zaanen","doi":"10.1080/00018732.2024.2369389","DOIUrl":"https://doi.org/10.1080/00018732.2024.2369389","url":null,"abstract":"These notes are based on lectures serving the advanced graduate education of the Delta Institute of Theoretical Physics in the Netherlands in autumn 2021. The goal is to explain in a language that ...","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142598228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Jan Zaanen – In memoriam","authors":"Paolo G. Radaelli","doi":"10.1080/00018732.2024.2407708","DOIUrl":"https://doi.org/10.1080/00018732.2024.2407708","url":null,"abstract":"In September 2022 Joerg Schmalian (then co-Editor in Chief for Advances in Physics) made an interesting proposal: he has seen on ArXiv a manuscript by Jan Zaanen, containing what Joerg described as...","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ambipolarity of hydrogen in matter revealed by muons","authors":"Ryosuke Kadono, Hideo Hosono","doi":"10.1080/00018732.2024.2413342","DOIUrl":"https://doi.org/10.1080/00018732.2024.2413342","url":null,"abstract":"Despite being the simplest element, hydrogen (H) exhibits complex behavior in materials due to its unique ambipolar character. In particular, it is recognized as one of the most important impurities in semiconductor physics, because H is often unintentionally incorporated into materials and significantly influences the electrical properties of the host material. One of the few means that have been applied to obtain experimental information about the local electronic state of diluted H is the use of muon (Mu) as pseudo-H. Here, we present an overview on the “ambipolarity model” that provides a new paradigm for the microscopic understanding of Mu-related defects. Its essence lies in the fact that the information Mu yields is not about the equilibrium double-charge transition level (<span><img alt=\"\" data-formula-source='{\"type\":\"image\",\"src\":\"/cms/asset/4fb9b511-84f4-4430-881c-e82bd3c5949c/tadp_a_2413342_ilm0001.gif\"}' src=\"//:0\"/></span><span><img alt=\"\" data-formula-source='{\"type\":\"mathjax\"}' src=\"//:0\"/><math><msup><mi>E</mi><mrow><mo>+</mo><mrow><mo>/</mo></mrow><mo>−</mo></mrow></msup></math></span>) but about the donor/acceptor levels (<span><img alt=\"\" data-formula-source='{\"type\":\"image\",\"src\":\"/cms/asset/966dd945-1120-4423-b15c-bd6c6842ed2c/tadp_a_2413342_ilm0002.gif\"}' src=\"//:0\"/></span><span><img alt=\"\" data-formula-source='{\"type\":\"mathjax\"}' src=\"//:0\"/><math><msup><mi>E</mi><mrow><mn>0</mn><mrow><mo>/</mo></mrow><mo>−</mo></mrow></msup></math></span> and <span><img alt=\"\" data-formula-source='{\"type\":\"image\",\"src\":\"/cms/asset/6566842e-e530-4827-8e46-e67008aa1fec/tadp_a_2413342_ilm0003.gif\"}' src=\"//:0\"/></span><span><img alt=\"\" data-formula-source='{\"type\":\"mathjax\"}' src=\"//:0\"/><math><msup><mi>E</mi><mrow><mo>+</mo><mrow><mo>/</mo></mrow><mo>−</mo><mn>0</mn></mrow></msup></math></span>) associated with the relaxed-excited states of Mu. Most notably, the model resolves serious discrepancies between the implications from implanted-Mu studies and theoretical predictions on the electronic state of H from <i>ab initio</i> density functional theory calculations in oxide semiconductors that have hindered the coherent integration of both Mu and H knowledge. The model also suggests that hydride state (H<span><img alt=\"\" data-formula-source='{\"type\":\"image\",\"src\":\"/cms/asset/06746f1c-06f4-4df6-ba2f-b1ebaac78308/tadp_a_2413342_ilm0004.gif\"}' src=\"//:0\"/></span><span><img alt=\"\" data-formula-source='{\"type\":\"mathjax\"}' src=\"//:0\"/><math><msup><mrow></mrow><mo>−</mo></msup></math></span>) plays important roles in oxide materials, as found in a variety of recent examples. Based on these successes, the model is currently serving as a reliable guide for the interpretation of various Mu states observed in other insulating materials, for which several recent examples are presented.","PeriodicalId":7373,"journal":{"name":"Advances in Physics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}