Article
Physics, Multidisciplinary
Jing He, Xiao-Qi Wang, Lian-Lian Zhang, Tong-Tong Xu, W. J. Gong
Summary: In this study, the impact of a quantum dot on Majorana-induced Andreev reflection was investigated. It was found that the quantum dot can have variable effects on the zero-bias conductance, suppressing reflection when non-superconducting with zero-energy level, and becoming dominant for the Majorana nonzero mode, including the zero-bias result.
Article
Physics, Multidisciplinary
Jinshuang Jin, Xin-Qi Li
Summary: A master equation approach is presented in this study to investigate transport through Majorana zero modes (MZMs). The comparison between the master equation treatment and the Bogoliubov-de Gennes (BdG) S-matrix scattering process reveals the intrinsic connection between both approaches and provides a better understanding of teleportation when the Majorana coupling vanishes. The study investigates the transient rates, occupation dynamics, currents, and shows the Markovian condition for the rates through bias voltage dependence.
NEW JOURNAL OF PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Chuanchang Zeng, Girish Sharma, Sumanta Tewari, Tudor Stanescu
Summary: By examining recent experiments on Majorana zero modes in semiconductor-superconductor heterostructures, the authors critically analyze the quantization of zero-bias differential conductance as a potential signature of Majorana physics in the presence of disorder. Through numerical calculations, they find that the large topological region associated with a clean system breaks up into smaller islands as disorder strength increases. These islands with approximately quantized zero-bias conductance demonstrate the presence of partially separated Majorana modes. Decreasing disorder leads to the coalescence of these islands into large topological regions. Observing islands with near quantized zero-bias conductance provides evidence for Majorana physics and serves as a diagnostic tool for evaluating disorder strength.
Article
Multidisciplinary Sciences
Michal Papaj, Liang Fu
Summary: The study presents a new approach to realizing Majorana bound states in two-dimensional superconducting systems based on spin-helical systems, offering a new path for the implementation of Majorana physics.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Matthew Otten, Keshav Kapoor, A. Baris Ozguler, Eric T. Holland, James B. Kowalkowski, Yuri Alexeev, Adam L. Lyon
Summary: This study investigates the correlation between the structure of quantum information and physical noise models in various quantum memory implementations. By numerical simulation and analysis, it provides comparisons between different types of quantum hardware and experimentally relevant formulas for the relative lifetimes of quantum information in different quantum memories. These findings have implications for the design of hybrid quantum devices.
Article
Quantum Science & Technology
W. W. Cheng, B. Li
Summary: We investigate the quantum temporal steering (TS) of a two-level system coupling to a nonequilibrium environment, and analyze the impact of various environmental parameters on TS behavior. We also explore the non-Markovianity of the system. Our results show that a nonequilibrium environment can enhance the quantum temporal steering of the two-level system, regardless of whether the system is experiencing Markovian or non-Markovian dynamics. Furthermore, a strong memory environment can significantly enhance TS. These findings highlight the potential for efficient manipulation of quantum system's temporal steering in a nonequilibrium environment.
QUANTUM INFORMATION PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Logan Gates, Alexander A. Penin
Summary: We investigate Majorana zero modes bound to giant vortices in topological superconductors or topological insulator/normal superconductor heterostructures. By expanding in inverse powers of a large winding number n, we obtain an analytic solution for nearly all n zero modes required by the index theorem. Contrary to existing estimates, the solution is not pinned to the vortex boundary and is composed of warped lowest Landau level states. While the dynamics shaping the zero modes is a delicate interference of magnetic effects and Andreev reflection, the solution is highly robust and determined by a single parameter, the vortex radius. The resulting local density of states exhibits several distinctive features that provide remarkable signatures for experimental observation of two-dimensional Majorana fermions.
Article
Quantum Science & Technology
Kevin J. Sung, Marko J. Rancic, Olivia T. Lanes, Nicholas T. Bronn
Summary: In this work, we use a noisy superconducting quantum processor to prepare Majorana zero modes (MZMs) as eigenstates of the Kitaev chain Hamiltonian, a model of non-interacting fermions. We extend error mitigation techniques to the case of general fermionic Gaussian states and demonstrate them by preparing MZMs on systems of up to seven qubits.
QUANTUM SCIENCE AND TECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Nikhil Harle, Oles Shtanko, Ramis Movassagh
Summary: This study demonstrates the identification and braiding of topological Majorana modes using a superconducting quantum processor, confirming their existence on quantum hardware and proposing a non-adiabatic technique for simulating braiding operations in topological quantum computing.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Piotr Stefanski
Summary: We theoretically investigate a tunneling junction between a normal electrode and a topological superconducting wire mediated by a quantum dot. We demonstrate that the presence of the quantum dot can be advantageous for identifying Majorana zero modes. Specifically, we show that when the dot is strongly coupled to the wire, the Majorana mode from the upper chiral sub-band leaks into the dot, providing additional information on Majorana mode formation. The characteristic three-peak structures in the spectral density of the dot in both spin sectors distinguish this scenario from the trivial one of a single Andreev resonance at the Fermi energy produced exclusively by the dot's spin sub-levels.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Daniele Guerci, Andrea Nava
Summary: In this study, transport across an interacting magnetic impurity coupled to the Majorana zero mode observed at the boundary of a topological superconductor is investigated. The hybridization of the Majorana zero mode with the quantum dot is observed in the presence of a finite tunneling amplitude. Notably, the topological regime is characterized by a vanishing Fano factor induced by the Majorana zero mode.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2021)
Article
Physics, Multidisciplinary
Tian-Yu He, Hailing Sun, Guofu Zhou
Summary: Weak QD-MZMs coupling at low temperatures enhances the thermopower and can be used to detect the presence of MZMs. The presence of a photon field decreases the electrical conductance, further enhancing the Seebeck effect.
FRONTIERS IN PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Ming Gong, Yijia Wu, Hua Jiang, Jie Liu, X. C. Xie
Summary: Motivated by recent experiments, this study establishes a portable scheme to uncover the non-Abelian statistics of vortex Majorana bound states (vMBSs) using normal fermionic modes. The charge flip signal of fermions, easily measurable through charge sensing, characterizes the non-Abelian statistics of vMBSs. A correction strategy is proposed to eliminate errors induced by unnecessary dynamical evolution of fermionic modes. A feasible protocol for performing non-Abelian braiding operations on vMBSs is also established.
Review
Physics, Multidisciplinary
Yijia Wu, Jie Liu, XinCheng Xie
Summary: In this review, we discuss the non-Abelian braiding properties of Majorana zero modes and topological Dirac fermionic modes, as well as their corresponding braiding schemes, with emphasis on the recent progress of topological Dirac fermionic modes.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2023)
Article
Materials Science, Multidisciplinary
Liu Yang, Alessandro Principi, Niels R. Walet
Summary: This article investigates the manipulation of Majorana zero modes in a thin film using a superconductor. The study analyzes nonadiabatic effects and proposes a method to increase the robustness of topological quantum computation by controlling the rotation frequency.
Article
Physics, Multidisciplinary
L. Banszerus, B. Frohn, T. Fabian, S. Somanchi, A. Epping, M. Mueller, D. Neumaier, K. Watanabe, T. Taniguchi, F. Libisch, B. Beschoten, F. Hassler, C. Stampfer
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Multidisciplinary
Daniel Zeuch, Fabian Hassler, Jesse J. Slim, David P. DiVincenzo
Article
Physics, Condensed Matter
Alexander Ziesen, Fabian Hassler
Summary: In this work, an alternative method based on perturbation theory is proposed to predict the low-energy states in vortex structures, providing concise analytical formulas with explicit magnetic-field and gap profiles. Results for both topological insulators and conventional electron gases are compared, discussing the impact of various parameters and offering a guide for future experiments. The findings are also compared to numerical results to validate the proposed method.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Physics, Multidisciplinary
Lisa Arndt, Fabian Hassler
Summary: This letter discusses the phenomenon of discrete time-translation symmetry breaking in periodically driven systems and proposes the use of quantum vacuum fluctuations to induce period multiplication. The authors demonstrate, using a circuit QED setup, that the system exhibits a nonequilibrium phase transition under weak dissipation or strong driving conditions.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Selma Franca, Viktor Koenye, Fabian Hassler, Jeroen van den Brink, Cosma Fulga
Summary: This study introduces a novel approach to exploring non-Hermitian physics involving reflection from the boundary of insulators, without the need for gain or loss. For strong topological insulators, the reflected waves exhibit non-Hermitian characteristics due to a reflection matrix exhibiting the non-Hermitian skin effect. This research expands the range of experimental platforms that can observe features associated with non-Hermitian topology.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Jurriaan Wouters, Fabian Hassler, Hosho Katsura, Dirk Schuricht
Summary: We study the phase diagram of an extended parafermion chain and show its equivalence to the non-chiral Z3 axial next-nearest neighbour Potts model. We discuss a possible experimental realization and find multiple gapped phases and a gapless phase.
SCIPOST PHYSICS CORE
(2022)
Article
Materials Science, Multidisciplinary
Ahmed Kenawy, Fabian Hassler, Roman-Pascal Riwar
Summary: Time-dependent control of superconducting quantum circuits is essential for scalable quantum hardware. This study investigates how electromotive force (emf) modifies the fractional Josephson effect and demonstrates it through current and charge measurements.
Article
Materials Science, Multidisciplinary
Lisa Arndt, Fabian Hassler
Summary: This article explores an alternative way of inducing a period-tripling transition in parametrically driven oscillators. The study shows that off-resonant frequency contributions can activate the parametric down-conversion and induce a period-tripling transition. Additionally, the research discusses the asymmetry between clockwise and counterclockwise rotating fixed points that arises beyond the rotating-wave approximation.
Article
Materials Science, Multidisciplinary
S. Franca, F. Hassler, I. C. Fulga
Summary: Periodically driven phases offer richer insights into nonequilibrium topology than static phases, but their realization is often hindered by decoherence effects. Reflection processes can simulate nontrivial Floquet phases in systems with higher-order topological phases, protected by a combination of local and spatial symmetries.
Article
Materials Science, Multidisciplinary
Hui Liu, Selma Franca, Ali G. Moghaddam, Fabian Hassler, Ion Cosma Fulga
Summary: We introduce a two-dimensional network model that realizes a higher-order topological phase (HOTP). In the HOTP, the bulk and boundaries of the system are gapped, and 16 corner states are protected by specific symmetries. Additionally, the model exhibits a strong topological phase at a point of maximal coupling, in contrast to conventional models. By introducing topological invariants, point group symmetry can protect a topological phase in a network. Our work lays the foundation for realizing HOTP in alternative experimental platforms using the network model.
Article
Physics, Multidisciplinary
Selma Franca, Fabian Hassler, Ion Cosma Fulga
Summary: In this study, we demonstrate that scattering from the boundary of static, higher-order topological insulators can simulate the behavior of Floquet topological insulators without the need for external driving. The unitary reflection matrix from the boundary of the HOTI is found to be topologically equivalent to a nontrivial Floquet operator in a lower dimension, and the concept of 'nested' scattering matrices is introduced to characterize the topology of the reflection matrix. This provides a promising approach for engineering topological Floquet systems in the lab while avoiding issues such as decoherence and heating.
SCIPOST PHYSICS CORE
(2021)
Article
Optics
Lisa Arndt, Fabian Hassler
Summary: At a bifurcation point, a small change in parameter causes a qualitative change in the system. Quantum fluctuations wash out this abrupt transition, enabling emission of quantized energy below the classical bifurcation threshold. A generic method is proposed to derive a characteristic function of photon counting close to a bifurcation threshold, based on the universality of the Martin-Siggia-Rose action.
Article
Materials Science, Multidisciplinary
Matteo Acciai, Fatemeh Hajiloo, Fabian Hassler, Janine Splettstoesser
Summary: This study investigates heat circulators controlled by a magnetic field and potentially superconducting phases to analyze the requirements for heat circulation in nonideal devices, finding that devices perform well as long as only a few transport channels are involved. The comparison between circulators with normal conducting contacts and those with superconducting contacts shows that the circulation coefficients remain essentially unchanged.
Article
Materials Science, Multidisciplinary
L. Gonzalez Rosado, F. Hassler, G. Catelani
Summary: By using a superconductor as a quantum mediator, the interaction range of solid-state spin qubits can be extended by over an order of magnitude, leading to exchange rates of up to 100 MHz. The geometry of the superconducting link offers room for optimization of the interaction range. However, strong spin-orbit scattering in the superconducting bulk is detrimental to the exchange interaction.
Article
Materials Science, Multidisciplinary
F. Hassler, A. Grabsch, M. J. Pacholski, D. O. Oriekhov, O. Ovdat, I Adagideli, C. W. J. Beenakker
