Article
Materials Science, Multidisciplinary
Donghao Liu, Zhan Cao, Xin Liu, Hao Zhang, Dong E. Liu
Summary: Efforts have been made to distinguish between Majorana zero modes (MZMs) and spatially separated quasi-Majorana modes (QMMs), both of which cause a quantized zero-bias peak in conductance measurement. A simple device utilizing a single nanowire was proposed to provide evidence of the topological Kondo effect in the topologically trivial phase with four QMMs, making it easier to distinguish Majorana and quasi-Majorana modes. Transport signatures are significantly different between the topological superconducting phase with MZMs and the topologically trivial phase with QMMs.
Article
Physics, Multidisciplinary
Sankar Das Sarma
Summary: Majorana particles, which are the same as their antiparticles, show promise for quantum computing in condensed matter systems. This article discusses the search for Majorana modes in semiconductor heterostructures and the limitations imposed by disorder. Majorana zero modes are emergent phenomena in topological superconductors, and this Perspective provides an overview of their physics, recent experimental progress, and future outlook for success.
Article
Materials Science, Multidisciplinary
Debashish Mondal, Arnob Kumar Ghosh, Tanay Nag, Arijit Saha
Summary: We theoretically investigate a practically realizable Floquet topological superconductor model based on a one-dimensional Rashba nanowire, which can generate multiple MEMs, and demonstrate the robustness of these MEMs in the presence of on-site time-independent random disorder potential.
Article
Physics, Multidisciplinary
A. P. Garrido, D. Zambrano, J. P. Ramos-Andrade, P. A. Orellana
Summary: We investigate the transport properties of a nanostructure composed of parallel double quantum dots coupled to normal contacts. Each quantum dot is connected to a topological superconducting nanowire with Majorana zero modes at its ends. The emergence of bound states and a transport suppression anomaly as a function of magnetic flux are found in symmetric configurations of the nanowires. The magnetic flux controls the projection of Majorana zero modes and bound states into the density of states and linear conductance, suggesting the potential manipulation of bound states by varying this parameter.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Materials Science, Multidisciplinary
Chun-Xiao Liu, Haining Pan, F. Setiawan, Michael Wimmer, Jay D. Sau
Summary: In this work, we propose a protocol for detecting the Majorana fusion rules in an artificial Kitaev chain and discuss the effects of realistic imperfections on the fusion outcomes. We also propose a fermion parity readout scheme and highlight the significance of these results for future experiments on detecting the non-Abelian properties of Majorana modes in a quantum dot chain.
Article
Physics, Multidisciplinary
P. Yu, J. Chen, M. Gomanko, G. Badawy, E. P. A. M. Bakkers, K. Zuo, V Mourik, S. M. Frolov
Summary: This study reports the observation of nearly quantized peaks close to the expected value by tunnel probes on both ends of a nanowire. However, the nearly quantized zero-bias peaks were only found localized to one end of the nanowire, raising doubts on whether they are Majoranas.
Article
Physics, Multidisciplinary
Natalia Chepiga, Nicolas Laflorencie
Summary: We study the Majorana chain with the shortest interaction term and hopping alternation, finding a rich phase diagram with six phases. We demonstrate that the Luttinger liquid phase terminates at a weaker interaction strength than the Ising critical line endpoint. We analyze topological properties through Majorana zero modes emergent in the two topological phases.
Article
Materials Science, Multidisciplinary
Haining Pan, Jay D. Sau, S. Das Sarma
Summary: In this study, we develop a theory for the three-terminal nonlocal conductance in Majorana nanowires in superconductor-semiconductor hybrid structures. We investigate whether nonlocal conductance can distinguish between trivial and topological Majorana scenarios in the presence of chemical potential inhomogeneity and random impurity disorder. The results show that the combination of local, nonlocal electrical, and thermal conductance measurements is necessary to accurately demonstrate topological Majorana zero modes in nanowires, as individual measurements may be influenced by disorder and heterogeneous potential.
Article
Materials Science, Multidisciplinary
Sankar Das Sarma, Haining Pan
Summary: This paper discusses the general issue of confirmation bias in experiments verifying various theoretical topological quantization predictions, using the recently retracted work by Zhang et al. and the related data from the Delft experiment as examples. It also analyzes a more recent nanowire experiment, showing that disorder may lead to misinterpretation of trivial zero-bias peaks as topological Majorana modes.
Article
Multidisciplinary Sciences
Marco Valentini, Maksim Borovkov, Elsa Prada, Sara Marti-Sanchez, Marc Botifoll, Andrea Hofmann, Jordi Arbiol, Ramon Aguado, Pablo San-Jose, Georgios Katsaros
Summary: Hybrid semiconductor-superconductor devices have great potential for realizing topological quantum computing with Majorana zero modes. However, the detection of Majorana modes based on either tunnelling or Coulomb blockade spectroscopy is still disputable. In this study, we propose an experimental protocol that allows us to perform both types of measurement on the same hybrid island, effectively reducing ambiguities in Majorana detections.
Article
Materials Science, Multidisciplinary
Olesia Dmytruk, Mircea Trif
Summary: We investigate the behavior of a topological superconducting nanowire with gliding Majorana zero modes under the influence of a microwave cavity field. We find that the decay rate of the cavity is determined by the parity encoded by the Majorana zero modes and their motion, even without any direct overlap of their wave functions. This is due to the interference between the extended bulk states that overlap with both Majorana states, which allows for momentum-resolved microwave spectroscopy and is modified by the gliding motion. We also demonstrate that these nonlocal effects are resistant to moderate disorder and validate our numerical calculations with an analytical low-energy model. Our approach provides an alternative method to tunneling spectroscopy for probing the nonlocal features associated with Majorana zero modes in nanowires.
Article
Materials Science, Multidisciplinary
Chao Lei, Guru Khalsa, Jiangfeng Du, Allan H. MacDonald
Summary: The study shows that in cylindrical cross-section semiconductor quantum wires, weak coupling exists between quasi-one-dimensional subbands, low-energy quasiparticles near the Fermi energy are nearly completely spin polarized, and the number of electrons in the active subbands of topological states is less than 10.
Article
Physics, Multidisciplinary
James Jun He, Yukio Tanaka, Naoto Nagaosa
Summary: Majorana fermions, as charge-neutral quasiparticles, exist on the boundaries of two-dimensional topological superconductors and generate enhanced local optical response. The features of local optical conductivity of chiral Majorana fermions distinguish them from trivial superconductors or insulators, as well as normal fermion edge states in quantum Hall systems. This provides a new applicable method to detect dispersive Majorana fermions and may lead to a novel direction in this research field.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Guan-Hao Feng, Hong-Hao Zhang
Summary: We propose a three-terminal structure to study robust signatures of Majorana zero modes. By observing the zero-bias differential conductance of the normal-metal lead at zero temperature, we can obtain information about Majorana braiding. The effect of thermal broadening is suppressed when the quantum dot is on resonance.
Article
Materials Science, Multidisciplinary
Haining Pan, Sankar Das Sarma
Summary: The study explores the properties of the superconductor-semiconductor nanowire hybrid Majorana platform in the presence of a deterministic slowly varying inhomogeneous chemical potential and a random quenched potential disorder. By calculating the tunnel conductance, the research examines the crossover among different mechanisms, with findings indicating the dominant role of random disorder in experiments.
Article
Physics, Multidisciplinary
Amrita Ghosh, Eytan Grosfeld
Summary: This study investigates the phases of hard-core bosons with weak topological insulator characteristics, highlighting their behavior at different densities. Results show the potential for experimental realization of both weak topological insulators at 1/4 and 3/4 densities, as well as charge-density-wave insulators at 1/2 filling, providing new directions for optical lattice experiments.
Article
Physics, Multidisciplinary
Abhishek Kumar, Gerardo Ortiz, Philip Richerme, Babak Seradjeh
Summary: This paper introduces the concept of a Floquet gauge pump, which utilizes a dynamically engineered Floquet Hamiltonian to uncover the inherent degeneracy of the ground state in interacting systems. Demonstrated in a one-dimensional XY model, the Floquet Hamiltonian in the high-frequency limit consists of static XY and dynamically generated DMI terms. The dynamically generated magnetization current depends on the phases of complex coupling terms, distinguishing between ordered and disordered phases.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Yantao Li, Adam Eaton, H. A. Fertig, Babak Seradjeh
Summary: We have discovered a new type of magic-angle phenomena when an AA-stacked graphene bilayer is twisted relative to another graphene system with band touching. At certain angles, multiple anisotropic Dirac cones coexist in the twisted multilayer structures, which we refer to as Dirac magic. The twist angle and perpendicular electric field can be used to tune the topological Lifshitz transitions induced by the anisotropy of the Dirac cones.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Paul Brookes, Tikai Chang, Marzena Szymanska, Eytan Grosfeld, Eran Ginossar, Michael Stern
Summary: Symmetry considerations play a crucial role in understanding the fundamental laws of nature and can protect quantum information from relaxation and decoherence.
PHYSICAL REVIEW APPLIED
(2022)
Article
Quantum Science & Technology
Daniel Dahan, Geva Arwas, Eytan Grosfeld
Summary: This study investigates the dissipative Bose-Hubbard model with chiral drive on a small ring of sites, exploring its long-time dynamical structure using mean-field equations and simulating the quantum master equation. The findings reveal that for sufficiently large drivings, the system exhibits a chaotic attractor at the mean-field level, presenting as a complex Wigner function at the quantum level. This behavior can be observed through the measurement of various bosonic correlation functions.
NPJ QUANTUM INFORMATION
(2022)
Article
Physics, Multidisciplinary
Shimon Arie Haver, Eran Ginossar, Sebastian E. de Graaf, Eytan Grosfeld
Summary: This study explores the potential of superconducting resonators as detectors for topological insulator nanowires by generating orbital resonances through the introduction of static and oscillating electromagnetic fields. The changes in the resonator's Q-factor as a function of the flux reveal the density of states, transition rules, and dependence on the applied flux of the surface 2D Dirac orbitals in the topological insulator nanowire.
COMMUNICATIONS PHYSICS
(2023)
Article
Physics, Multidisciplinary
Devendra Singh Bhakuni, Amrita Ghosh, Eytan Grosfeld
Summary: This study explores the effect of many-body interactions in mirror-symmetry protected topological crystalline insulators. It demonstrates the stability of the mirror-symmetry protected topological phase under short-range interactions and the interaction-induced topological phase transition when longer-range interactions are introduced.
SCIPOST PHYSICS CORE
(2022)
Article
Materials Science, Multidisciplinary
Adam Eaton, Yantao Li, H. A. Fertig, Babak Seradjeh
Summary: This study investigates the presence of flat bands in stacked graphene multilayers with small relative twist angles. The effect of Dirac point asymmetry and Fermi velocity differences between layers is considered. The results show that despite this asymmetry, the flat band phenomenon persists. The magic angles can be tuned by controlling the screening in the bilayer system or the twist angles of the outer layers in the tetralayer system. Notably, the quantitative values of the magic angles are increased in the models.
Article
Materials Science, Multidisciplinary
Ruchi Saxena, Eytan Grosfeld, Sebastian E. de Graaf, Tobias Lindstrom, Floriana Lombardi, Oindrila Deb, Eran Ginossar
Summary: We analyze the confinement of electronic surface states in a model of a topological insulator nanowire. We show that intentional backscattering can be induced in the presence of a nanowire constriction and propose a geometry involving two constrictions that form effective barriers for the formation of a quantum dot. By analyzing the noninteracting electronic transport through the device, we demonstrate how externally applied magnetic flux and electrostatic gates can control the spectrum of the quantum dot and the electronic transport through the surface states of the model device.
Article
Quantum Science & Technology
E. Lupo, E. Grosfeld, E. Ginossar
Summary: We propose a voltage gate-based method for controlling the Majorana transmon and analyze its performance in terms of qubit control errors and charge noise effects. The results show that the method achieves high-fidelity single-qubit rotation gates in both the laboratory frame and the qubit rotating frame. Furthermore, the system exhibits long dephasing times at the sweet spots and remarkable resilience to charge noise in the driven case.
Article
Physics, Multidisciplinary
V. Alan Kostelecky, Ralf Lehnert, Navin McGinnis, Marco Schreck, Babak Seradjeh
Summary: This paper proposes a correspondence between emergent Lorentz symmetry in condensed-matter systems and the effective field theory for Lorentz violation in fundamental theories of spacetime and matter. The consequences of this correspondence on the spectral and transport properties of Dirac and Weyl semimetals are investigated, and the bulk-boundary correspondence between bulk topological invariants and drumhead surface states of these semimetals is demonstrated.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Amrita Ghosh, Eytan Grosfeld
Summary: Through the use of QMC technique, it was discovered that hard-core bosons on the honeycomb lattice exhibit a dimer insulator phase near maximum anisotropy, characterized by a topological entanglement entropy ln(2)/2, indicative of a fractional quantum Hall state. The presence of edge states was identified, and a QMC-based method was derived to extract and verify their chirality, all without the need for magnetic flux or lattice frustration.
Article
Physics, Multidisciplinary
Yantao Li, H. A. Fertig, Babak Seradjeh
PHYSICAL REVIEW RESEARCH
(2020)
Article
Materials Science, Multidisciplinary
D. Dahan, E. Grosfeld, B. Seradjeh
Article
Materials Science, Multidisciplinary
Abhishek Kumar, M. Rodriguez-Vega, T. Pereg-Barnea, B. Seradjeh