Complete description of fault-tolerant quantum gate operations for topological Majorana qubit systems

Scheppe, Adrian; Pak, Michael V.

doi:10.1103/physreva.105.012415

Cited by 4 publications

(3 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…he Josephson junction (JJ) composed of a topological insulator (TI) is intensively studied as a platform to demonstrate topological superconductivity, which is one of the possible routes to realize Majorana particles [1][2][3] for future fault-tolerant Majorana qubits. [4][5][6][7] As for the topological superconductors, while nanowire-based approaches with magnetic fields are advanced, 9,10) another approach using one-dimensional conducting states protected by timereversal symmetry in topological insulators (TI) or higherorder topological insulators (HOTI) is becoming an alternative option for hosting Majorana particles. 11) The advantage of the TI approach is that they are expected to host single-mode conduction and exhibit insensitivity to disorder, as well as no requirement for applied magnetic fields.…”

mentioning

confidence: 99%

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Ohtomo¹,

Deacon²,

Hosoda³

et al. 2022

Appl. Phys. Express

View full text Add to dashboard Cite

We report on the fabrication of Josephson junction devices with weak links utilizing the Weyl and higher-order topological semimetal WTe2. We show that WTe2/Pd contact annealed at a low temperature of 80°C did not exhibit superconducting properties because neither WTe2 nor Pd are superconductors in the ground state. Upon 180°C annealing, spontaneous formation of superconducting PdTe due to Pd diffusion enabled us to obtain the interface between WTe2 and superconductor suitable for the Josephson junction. This result is a facile technique to make a Josephson junction and induce Cooper pairs into topological telluride semimetals.

show abstract

mentioning

confidence: 99%

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Ohtomo¹,

Deacon²,

Hosoda³

et al. 2022

Appl. Phys. Express

View full text Add to dashboard Cite

show abstract

“…The quantum computer, which is based on the quantum-entangled superpositions of individual quantum systems, is expected to surpass conventional computers in terms of information and processing capabilities. , However, one of the challenges for future fault-tolerant quantum computing is the enormous overhead in the number of additional qubits and gate operations required for error-correction techniques to overcome the unavoidable noise due to the interaction with the environment. Another approach to dealing with noise is to make use of topological states of matter. − Topological quantum computation implements unitary quantum gates by braiding topologically protected objects that obey non-Abelian statics. If the braiding operations are slow in comparison to the inverse of the energy gap and external perturbations are insufficient to close the gap, the system remains topologically resilient to disturbances and noise.…”

Section: Introductionmentioning

confidence: 99%

Quantum Spin Hall States in 2D Monolayer WTe₂/MoTe₂ Lateral Heterojunctions for Topological Quantum Computation

Ohfuchi

Sekine

2023

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

The quantum spin Hall (QSH) states in two-dimensional topological insulators (2DTIs) are expected to be applied to future topological quantum computation. We investigate the two-dimensional (2D) lateral heterojunctions of the monolayer 1T′–WTe2 as a 2DTI and the monolayer 2H–MoTe2 as a topologically trivial insulator using density functional theory. This 2D material is expected to have QSH states at each periodically arranged junction as well as properties distinct from the individual properties of each constituent material. At heterojunctions perpendicular to the dimer chains of W atoms in 1T′–WTe2 (in the y direction), two pairs of helical (QSH) states, one at each junction, connect the valence and conduction bands. The strain induced by the large lattice mismatch of the two materials in the y direction widens the bandgap of the 1T′–WTe2 monolayer as a QSH insulator. In the case of the heterojunctions in the x direction, the difference in atomic structure between the two junctions due to low symmetry creates an energy difference between two helical states and a potential gradient in the wide-bandgap 2H–MoTe2 region, resulting in various junction-localized bands. The widening bandgap of the heterojunctions in the y direction is essential for electronic applications of the QSH states, suggesting that this 2D material, namely, 2D WTe2/MoTe2 heterojunctions, can be a promising candidate for integrating Majorana qubits for future topological quantum computation.

show abstract

“…Cooper pairs [1,2]. It is widely known that the condensate that arises from this reformulation of the ground state is ultimately responsible for the mysterious behavior exhibited by such systems, and it is due to these qualities, that such materials find themselves at the center of several astonishing quantum technological fetes such as regular and fault tolerant qubits [3][4][5], phase engineered Josephson junctions [6], topological heterostructure electronics [7], and so on. So, it seems currently that the superconductor (SC) will form the backbone of technology leading into the future, and, for this reason, we are sufficiently motivated to streamline our search and synthesis of such materials.…”

Section: Introductionmentioning

confidence: 99%

Perturbing finite temperature multicomponent DFT 1D Kohn–Sham systems: Peierls gap & Kohn anomaly

Scheppe,

Pak

2023

J. Phys.: Condens. Matter

Self Cite

View full text Add to dashboard Cite

One of the greatest challenges when designing new technologies that make use of non-trivial quantum materials is the difficulty associated with predicting material-specific properties, such as critical temperature, gap parameter, etc. There is naturally a great amount of interest in these types of condensed matter systems because of their application to quantum sensing, quantum electronics, and quantum computation; however, they are exceedingly difficult to address from first principles because of the famous many-body problem. For this reason, a full electron-nuclear quantum calculation will likely remain completely out of reach for the foreseeable future. A practical alternative is provided by finite temperature, multi component density functional theory, which is a formally exact method of computing the equilibrium state energy of a many-body quantum system. In this work, we use this construction alongside a perturbative scheme to demonstrate that the phenomena Peierls effect and Kohn anomaly are both natural features of the Kohn–Sham (KS) equations without additional structure needed. We find the temperature dependent ionic density for a simple 1D lattice which is then used to derive the ionic densities temperature dependent affect on the electronic band structure. This is accomplished by Fourier transforming the ionic density term found within this KS electronic equation. Using the Peierls effect phonon distortion gap openings in relation to the Fermi level, we then perturb the KS ionic equation with a conduction electron density, deriving the Kohn anomaly. This provides a workable predictive strategy for interesting electro-phonon related material properties which could be extended to 2D and 3D real materials while retaining the otherwise complicated temperature dependence.

show abstract

Complete description of fault-tolerant quantum gate operations for topological Majorana qubit systems

Cited by 4 publications

References 30 publications

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Quantum Spin Hall States in 2D Monolayer WTe₂/MoTe₂ Lateral Heterojunctions for Topological Quantum Computation

Perturbing finite temperature multicomponent DFT 1D Kohn–Sham systems: Peierls gap & Kohn anomaly

Contact Info

Product

Resources

About

Complete description of fault-tolerant quantum gate operations for topological Majorana qubit systems

Cited by 4 publications

References 30 publications

Josephson junctions of Weyl semimetal WTe2 induced by spontaneous nucleation of PdTe superconductor

Josephson junctions of Weyl semimetal WTe2 induced by spontaneous nucleation of PdTe superconductor

Quantum Spin Hall States in 2D Monolayer WTe2/MoTe2 Lateral Heterojunctions for Topological Quantum Computation

Perturbing finite temperature multicomponent DFT 1D Kohn–Sham systems: Peierls gap & Kohn anomaly

Contact Info

Product

Resources

About

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Josephson junctions of Weyl semimetal WTe₂ induced by spontaneous nucleation of PdTe superconductor

Quantum Spin Hall States in 2D Monolayer WTe₂/MoTe₂ Lateral Heterojunctions for Topological Quantum Computation