Article
Multidisciplinary Sciences
Haoyu Hu, Qimiao Si
Summary: Flat bands enhance correlation effects and have gained significant attention. They offer a platform to explore topology in correlated systems and correlation physics enriched by topology. Recent experiments in correlated kagome metals have observed strange-metal behavior. The challenge lies in studying the impact of local Coulomb repulsion when band topology hinders a real-space description. In a modified kagome lattice, we have discovered an orbital-selective Mott transition in any system with coupled topological flat and wide bands. This is made possible through the use of exponentially localized and Kramers-doublet Wannier functions, leading to an effective Kondo-lattice description. Our findings shed light on the formation and destruction of quasiparticles in such coupled topological flat-wide band systems, providing a conceptual framework to understand the strange-metal properties in kagome metals and beyond.
Article
Chemistry, Physical
V. S. Stolyarov, V. A. Sheina, D. A. Khokhlov, S. Vlaic, S. Pons, H. Aubin, R. S. Akzyanov, A. S. Vasenko, T. Menshchikova, E. Chulkov, A. A. Golubov, T. Cren, D. Roditchev
Summary: The study demonstrates the nesting-induced splitting of coherent scattering vectors in three-dimensional topological insulator Bi2Te3, which shows a unique evolution in energy. This effect becomes experimentally observable when the lifetime of quasiparticles shortens due to disorder. The amplitude of the splitting can be used to evaluate the lifetime of electrons and should be observed in any system with a well-defined scattering vector regardless of its topological properties.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Yuan Fang, Huali Zhang, Ding Wang, Guowei Yang, Yi Wu, Peng Li, Zhiguang Xiao, Tianyun Lin, Hao Zheng, Xiao-Long Li, Huan-Hua Wang, Fanny Rodolakis, Yu Song, Yilin Wang, Chao Cao, Yang Liu
Summary: This study reveals the spectroscopic signature of the interaction between Kondo-like screening and long-range magnetic order in a Hund metal MnSi, demonstrating the coexistence and competition of spin/orbital coherence with magnetic order, resulting in a weak itinerant ferromagnet.
Article
Materials Science, Multidisciplinary
Jolanta Stankiewicz, Pedro Schlottmann, Javier Blasco, Monica Ciomaga Hatnean, Geetha Balakrishnan
Summary: We conducted an impedance study on SmB6 single crystals in-plane and out-of-plane at low temperatures and a wide frequency range. The dielectric behavior of the system, ranging from surface to bulk dominated electrical conduction, was described by a universal equivalent circuit between 2 and 10 K. We identified the contributions of resistance, capacitance, and inductance to the impedance. The obtained equivalent inductance decreased significantly with increasing temperature, indicating the transition to bulk controlled electrical conduction. Self-sustained voltage oscillations below 6 K, observed when applying a dc current to small crystals, suggest a large self-capacitance of SmB6 likely due to surface states.
MATERIALS RESEARCH BULLETIN
(2023)
Review
Physics, Applied
Oliver Breunig, Yoichi Ando
Summary: Topological insulators are unique materials that result in unconventional quantum phenomena. To observe these phenomena experimentally, sophisticated devices are required. This Technical Review discusses various physics effects that can be observed in carefully fabricated devices, including topological superconductivity, quantum anomalous Hall states, spintronic functionalities and topological mesoscopic physics.
NATURE REVIEWS PHYSICS
(2022)
Article
Physics, Multidisciplinary
Peize Ding, Tilman Schwemmer, Ching Hua Lee, Xianxin Wu, Ronny Thomale
Summary: We study the quasiparticle interference (QPI) pattern caused by adjacent impurities on the surface of a gapped superconductor (SC). We find that hyperbolic fringes (HFs) can appear in the QPI signal due to the loop contribution of two-impurity scattering, with the impurity locations as the hyperbolic focus points. For single pocket Fermiology, a HF pattern indicates chiral SC order with nonmagnetic impurities, and requires magnetic impurities for nonchiral SC. For multipocket scenario, a sign-changing order parameter like an s± wave also produces a HF signature. We discuss twin impurity QPI as a new tool to supplement the analysis of superconducting order from local spectroscopy.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Steven A. H. de Rooij, Jochem J. A. Baselmans, Vignesh Murugesan, David J. Thoen, Pieter J. de Visser
Summary: The experiment measures temperature-dependent quasiparticle fluctuations in a small Al volume embedded in a NbTiN superconducting microwave resonator. It was found that at lower temperatures, the recombination time saturates and the fluctuation level decreases by a factor of 100. The number of free quasiparticles is still thermal, contrary to the theoretical inverse relation between quasiparticle number and recombination time, likely due to quasiparticle trapping.
Article
Physics, Multidisciplinary
Debmalya Chakraborty, Annica M. Black-Schaffer
Summary: This study demonstrates that quasiparticle interference (QPI) can serve as a direct experimental probe of bulk odd-frequency superconducting pairing. Using Fourier transform scanning tunneling microscopy and spectroscopy, the study shows that the nature of QPI peaks can only be characterized by including the odd-frequency pairing correlations generated in the system, particularly identifying the defining feature of odd-frequency pairing as a bias asymmetry in QPI, which is present in materials with odd-frequency pairing regardless of its origin.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Linghan Zhu, Haonan Wang, Li Yang
Summary: In this study, we reveal a remarkable many-electron effect where doped carriers form a 2D plasmon and strongly couple with quasiparticles to renormalize moire potential and achieve ultra-flat bands. We demonstrate this effect in twisted MoS2/WS2 heterobilayer and predict that doping can effectively control the competition between correlated mechanisms, potentially leading to a quantum transition between Mott and charge-transfer insulating states.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
D. A. Khokhlov, R. S. Akzyanov
Summary: In this study, theoretical investigation of quasiparticle interference in superconducting topological insulators reveals that interference patterns exhibit nematic behavior for small bias voltages and are sensitive to the orientation of the nematicity. The violation of rotational symmetry is observed in both coordinate and momentum spaces, with interference patterns resembling those of the normal state when the bias voltage is comparable to the order parameter value. The results are compared with existing experimental data.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2021)
Article
Physics, Multidisciplinary
R. L. Willett, K. Shtengel, C. Nayak, L. N. Pfeiffer, Y. J. Chung, M. L. Peabody, K. W. Baldwin, K. W. West
Summary: In this study, we provide experimental evidence for the non-Abelian nature of excitations at v = 7/2 by measuring resistance oscillations in Fabry-Pérot interferometers using new high-purity heterostructures. We also examine the fermion parity of non-Abelian quasiparticles at both v = 5/2 and v = 7/2 for the first time. These findings support the utility of e/4 quasiparticles for topological quantum computation.
Article
Physics, Multidisciplinary
Sourav Biswas, Rajarshi Bhattacharyya, Hemanta Kumar Kundu, Ankur Das, Moty Heiblum, Vladimir Umansky, Moshe Goldstein, Yuval Gefen
Summary: The fractional charge of quasiparticles is a fundamental feature of quantum Hall effect states. At sufficiently low temperatures, the Fano factor is found to be equal to the bulk filling factor, and this noise pattern is also observed on intermediate conductance plateaux.
Article
Multidisciplinary Sciences
Chi Ming Yim, Dibyashree Chakraborti, Luke C. Rhodes, Seunghyun Khim, Andrew P. Mackenzie, Peter Wahl
Summary: Exploiting inversion symmetry breaking in systems with strong spin-orbit coupling allows for spin control through electric fields, requiring specific conditions for a two-dimensional electron gas. Recent studies have shown a large Rashba spin splitting on the transition metal oxide terminations, indicating a different orbital effect that raises questions about quasiparticle scattering. The spin-orbital selection rules relevant for conventional Rashba systems are demonstrated to be true spin selection rules in this correlated electron liquid, with the spin coherence length determined through quasiparticle interference imaging.
Article
Materials Science, Multidisciplinary
Vardan Kaladzhyan, Frederic Joucken, Zhehao Ge, Eberth A. Quezada-Lopez, Takashi Taniguchi, Kenji Watanabe, Jairo Velasco, Cristina Bena
Summary: The study calculates the form of quasiparticle interference patterns in bilayer graphene, incorporating trigonal warping terms perturbatively. By introducing four types of impurities localized on different sublattices, closed-form analytical expressions for the oscillatory corrections to the local density of states are obtained both in real and Fourier spaces. Comparison with recent experimental and semianalytical T-matrix results shows good agreement between the findings, previous results, and experimental data.
Article
Chemistry, Physical
Seung-Ju Hong, Jae-Mo Lihm, Cheol-Hwan Park
Summary: Using T-matrix theory, this study shows that the assumption of independence of quasiparticle interference patterns in momentum space with the strength of the impurity potential breaks down. A rich, impurity-strength-dependent structure in the QPI pattern of TaAs is predicted, emphasizing the importance of considering the details of the scattering impurity in interpreting Fourier-transform scanning tunneling spectroscopy experiments.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Review
Physics, Condensed Matter
Lukas Janssen, Matthias Vojta
JOURNAL OF PHYSICS-CONDENSED MATTER
(2019)
Article
Physics, Multidisciplinary
Mary Madelynn Nayga, Stephan Rachel, Matthias Vojta
PHYSICAL REVIEW LETTERS
(2019)
Article
Materials Science, Multidisciplinary
Pedro M. Consoli, Lukas Janssen, Matthias Vojta, Eric C. Andrade
Article
Materials Science, Multidisciplinary
Eric C. Andrade, Lukas Janssen, Matthias Vojta
Article
Materials Science, Multidisciplinary
Santanu Dey, Eric C. Andrade, Matthias Vojta
Article
Materials Science, Multidisciplinary
Seung-Ho Baek, Hyeon Woo Yeo, Seung-Hwan Do, Kwang-Yong Choi, Lukas Janssen, Matthias Vojta, Bernd Buechner
Article
Materials Science, Multidisciplinary
Shouryya Ray, Matthias Vojta, Lukas Janssen
Article
Materials Science, Multidisciplinary
S. Gass, P. M. Consoli, V Kocsis, L. T. Corredor, P. Lampen-Kelley, D. G. Mandrus, S. E. Nagler, L. Janssen, M. Vojta, B. Buechner, A. U. B. Wolter
Article
Materials Science, Multidisciplinary
Seydou-Samba Diop, Lars Fritz, Matthias Vojta, Stephan Rachel
Article
Materials Science, Multidisciplinary
Lukas Janssen, Stefan Koch, Matthias Vojta
Article
Materials Science, Multidisciplinary
Santanu Dey, Eric C. Andrade, Matthias Vojta
Article
Materials Science, Multidisciplinary
Heike Eisenlohr, Seung-Sup B. Lee, Matthias Vojta
Article
Materials Science, Multidisciplinary
G. Bastien, M. Roslova, M. H. Haghighi, K. Mehlawat, J. Hunger, A. Isaeva, T. Doert, M. Vojta, B. Buechner, A. U. B. Wolter
Article
Materials Science, Multidisciplinary
Urban F. P. Seifert, Matthias Vojta
Article
Materials Science, Multidisciplinary
Shouryya Ray, Matthias Vojta, Lukas Janssen