Article
Materials Science, Multidisciplinary
Omri Lesser, Yuval Oreg, Ady Stern
Summary: This article introduces a method for inducing topological superconductivity in Josephson junctions without applying any magnetic fields. The method is based on two key factors: phase winding in superconductor-normal-superconductor junctions and asymmetry in Fermi velocities. The critical curves for topological phase transitions are derived analytically and confirmed through numerical calculations. Material platforms with experimental feasibility are also proposed.
Article
Materials Science, Multidisciplinary
Alfonso Maiellaro, Francesco Romeo, Roberta Citro, Fabrizio Illuminati
Summary: Squashed entanglement and quantum conditional mutual information are reliable measures of bipartite quantum correlations, able to capture fine-grain structures of quantum systems. By introducing the concept of quantum conditional mutual information between the edges of quantum many-body systems, we demonstrate that it characterizes one-dimensional topological insulators and superconductors and converges to a quantized topological invariant, even in the presence of disorder or interactions. We conjecture that it coincides with the edge-to-edge squashed entanglement in the entire ground-state phase diagram of symmetry-protected topological systems.
Article
Multidisciplinary Sciences
Pengjie Wang, Guo Yu, Yves H. Kwan, Yanyu Jia, Shiming Lei, Sebastian Klemenz, F. Alexandre Cevallos, Ratnadwip Singha, Trithep Devakul, Kenji Watanabe, Takashi Taniguchi, Shivaji L. Sondhi, Robert J. Cava, Leslie M. Schoop, Siddharth A. Parameswaran, Sanfeng Wu
Summary: In this study, 2D arrays of 1D Luttinger liquids (LLs) with crystalline quality were realized in twisted bilayer tungsten ditelluride (tWTe(2)). The nanoscale distance between parallel 1D electronic channels in the moire pattern of tWTe(2) is tunable by the interlayer twist angle, resulting in a large transport anisotropy. The observed power-law scaling behavior suggests the formation of a 2D anisotropic phase resembling an array of LLs.
Article
Physics, Multidisciplinary
Colin Rylands, Pasquale Calabrese, Bruno Bertini
Summary: A gas of interacting fermions confined in a quasi one-dimensional geometry undergoes a crossover from a Bose–Einstein condensate (BEC) to Bardeen–Cooper–Schrieffer (BCS) superfluidity by varying the coupling constant. We study the quench process where the coupling constant is suddenly changed from the BEC to the BCS value, and show that the local stationary state after the quench can be exactly determined using the quench action approach. We provide experimentally accessible characterizations of the stationary state by computing the local pair correlation function and the quasiparticle distribution functions.
PHYSICAL REVIEW LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Yutao Li, Scott Dietrich, Carlos Forsythe, Takashi Taniguchi, Kenji Watanabe, Pilkyung Moon, Cory R. Dean
Summary: By utilizing dielectric patterning to subject graphene to a one-dimensional electrostatic superlattice, multiple Dirac cones are observed, demonstrating the ability to induce tunable anisotropy in high-mobility two-dimensional materials. This offers a new approach to engineering flat energy bands where electron interactions can lead to emergent properties, which is desired for novel electronic and optical applications.
NATURE NANOTECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Pavel E. Dolgirev, Yi-Fan Qu, Mikhail B. Zvonarev, Tao Shi, Eugene Demler
Summary: The Fermi-polaron problem involves the interaction between a mobile impurity and a fermionic medium, with conventional expectations suggesting dissipative dynamics, but research in a one-dimensional system has revealed a different type of polaron dynamics.
Article
Chemistry, Physical
Wenbin Wu, Zeping Shi, Yuhan Du, Yuxiang Wang, Fang Qin, Xianghao Meng, Binglin Liu, Yuanji Ma, Zhongbo Yan, Mykhaylo Ozerov, Cheng Zhang, Hai-Zhou Lu, Junhao Chu, Xiang Yuan
Summary: The manuscript reports experimental observations of a Lifshitz transition in a topological insulator HfTe5 under a strong magnetic field, leading to the formation of one-dimensional Weyl modes in a three-dimensional material. By tracking the Landau level transitions, the study demonstrates that band inversion drives the crossing of zeroth Landau bands and the formation of a one-dimensional Weyl mode. This transition occurs at 21 T and moves the Weyl mode close to the Fermi level.
Article
Optics
F. Chevy, G. Orso
Summary: In this article, we discuss the accuracy of 1D effective theories in describing the behavior of ultracold atomic ensembles confined in quantum wires. By using a fully many-body approach, we derive the effective Hamiltonian for these systems and calculate the beyond-mean-field corrections to the ground state energy caused by virtual transitions to the excited state of the confining potential. We find that effective finite-range corrections are one order of magnitude larger than effective three-body interactions, due to the Pauli principle. Comparing with exact solutions of the purely 1D problem, we conclude that a 1D effective theory provides a good description of the ground state for a wide range of interaction parameters.
Article
Optics
Oleksandr Gamayun, Milosz Panfil, Felipe Taha Sant'Anna
Summary: In this paper, we study the McGuire model of a one-dimensional gas of free fermions interacting with a single impurity, and compute the static one-body function and momentum distribution of the impurity at finite temperatures. The results involve averages over Fredholm determinants, which we further analyze using the effective form factors approach. With this approach, we derive the large-distance behavior of the one-body function, which exhibits an averaged exponential decay. This method allows us to study the experimentally important regime of small momenta of the impurity's momentum distribution, and we also calculate the finite-temperature Tan's contact.
Article
Optics
Damian Wlodzynski
Summary: A method for numerically exact calculation is proposed in this article for a mixture with a single impurity and several majority fermions in a harmonic potential. The method separates one degree of freedom through a tailored canonical transformation and performs exact diagonalization on the simplified Hamiltonian. This method is particularly effective for heavy impurities.
Article
Physics, Multidisciplinary
Alex Turzillo, Minyoung You
Summary: This study investigates the boundary supersymmetry of one-dimensional fermionic phases beyond SPT phases, calculating the number of protected boundary supercharges based on bulk phase invariants. Using the connection between Majorana edge modes and real supercharges, the researchers were able to derive this information.
PHYSICAL REVIEW LETTERS
(2021)
Article
Astronomy & Astrophysics
A. Alonso Izquierdo, J. Queiroga-Nunes, L. M. Nieto
Summary: In this paper, numerical investigations were conducted on the scattering between a wobbling kink and a wobbling antikink in the standard phi(4) model. The study discussed the dependence of final velocities, wobbling amplitudes, and frequencies of the scattered kinks on collision velocity and initial wobbling amplitude. The fractal structure becomes more intricate with the emergence of new resonance windows and the splitting of those arising in non-excited kink scattering. Outside this phase, the final wobbling amplitude shows a linear dependence on collision velocity, which is almost independent of the initial wobbling amplitude.
Article
Astronomy & Astrophysics
Danial Saadatmand, Herbert Weigel
Summary: We investigate the quantum effects of kink solitons constructed by coupling to an excited fermion bound state. Our study is based on the semiclassical expansion and treats the energy of a single level and the Dirac sea equally. For these kink solutions, we calculate the energy of the Dirac sea as the fermion vacuum polarization energy. We find that it is substantial and typically outweighs the energy gain from binding the single level.
Article
Astronomy & Astrophysics
Jarah Evslin, Hengyuan Guo
Summary: This study presents the two-loop kink mass and ground state construction in a scalar field theory, utilizing a simplified calculation method and eliminating the need for regulator matching conditions. The use of a coherent state operator and a perturbative fixed kink momentum greatly simplifies the process.
Article
Physics, Multidisciplinary
Ipsita Das, Cheng Shen, Alexandre Jaoui, Jonah Herzog-Arbeitman, Aaron Chew, Chang-Woo Cho, Kenji Watanabe, Takashi Taniguchi, Benjamin A. Piot, B. Andrei Bernevig, Dmitri K. Efetov
Summary: The discovery of flat bands with nontrivial band topology in magic-angle twisted bilayer graphene (MATBG) has provided a unique platform to study strongly correlated phenomena including superconductivity, correlated insulators, Chern insulators, and magnetism. The high magnetic field Hofstadter spectrum in MATBG reveals reentrant correlated insulators and interaction-driven Fermi-surface reconstructions, indicating a qualitatively new Hofstadter spectrum arising due to the strong electronic correlations in the reentrant flat bands.
PHYSICAL REVIEW LETTERS
(2022)