Charge qubits based on ultra-thin topological insulator films

Abstract

We study how to use the surface states in a Bi${}_2$Se${}_3$ topological insulator ultra-thin film that are affected by finite size effects for the purpose of quantum computing. We demonstrate that: (i) surface states under the finite size effect can effectively form a two-level system where their energy levels lie in between the bulk energy gap and a logic qubit can be constructed, (ii) the qubit can be initialized and manipulated using electric pulses of simple forms, (iii) two-qubit entanglement is achieved through a $\sqrt{\text{SWAP}}$ operation when the two qubits are in a parallel setup, and (iv) alternatively, a Floquet state can be exploited to construct a qubit and two Floquet qubits can be entangled through a Controlled-NOT operation. The Floquet qubit offers robustness to background noise since there is always an oscillating electric field applied, and the single qubit operations are controlled by amplitude modulation of the oscillating field, which is convenient experimentally.

arXiv comment12 pages, 9 figures, submitted to the journal Frontiers of Physics

References in corpus (25)

• Topological Insulators
• Topological Insulator Materials
• Photovoltaic Hall effect in graphene
• Observation of Floquet-Bloch states on the surface of a topological insulator
• Spintronics and Pseudospintronics in Graphene and Topological Insulators
• Floquet Engineering of Quantum Materials
• Model Hamiltonian for Topological Insulators
• Three-Dimensional Topological Insulators
• Massive Dirac fermions and spin physics in an ultrathin film of topological insulator
• Oscillatory crossover from two dimensional to three dimensional topological insulators
• Charge-qubit operation of an isolated double quantum dot
• Anomalous Finite Size Effects on Surface States in the Topological Insulator Bi${}_2$Se${}_3$
• Electrically tunable surface-to-bulk coherent coupling in topological insulator thin films
• Scattering Theory for Floquet-Bloch States
• Magnetically Defined Qubits on 3D Topological Insulators
• Topological Floquet-Thouless energy pump
• Weak localization and weak anti-localization in topological insulators
• Sound-driven single-electron transfer in a circuit of coupled quantum rails
• Topological insulator quantum dot with tunable barriers
• Floquet-engineered quantum state manipulation in a noisy qubit
• Optical response of a topological-insulator--quantum-dot hybrid interacting with a probe electric field
• Low temperature saturation of phase coherence length in topological insulators
• Impurity scattering on the surface of topological insulator thin films
• Entanglement generation via power-of-SWAP operations between dynamic electron-spin qubits
• Protocol for Fermionic Positive-Operator-Valued Measures