Quantum computation with two-dimensional graphene quantum dots

Abstract

We study an array of graphene nano sheets that form a two-dimensional S = 1/2 Kagome spin lattice used for quantum computation. The edge states of the graphene nano sheets are used to form quantum dots to confine electrons and perform the computation. We propose two schemes of bang-bang control to combat decoherence and realize gate operations on this array of quantum dots. It is shown that both schemes contain a great amount of information for quantum computation. The corresponding gate operations are also proposed.

An approach to controlling the fluorescence of graphene quantum dots: From surface oxidation to fluorescent mechanism

“…Generally, the periphery of micrometer-sized graphene sheets consists of zigzag and armchair edges and free edges that coexist with functionalized edges. [34,35] It is proposed that the luminescence of GQDs should originate from free zigzag sites with a carbene-like triplet ground state. The carbene centers at zigzag sites are stabilized by the localization of itinerant π electrons through σ -π coupling.…”

Double quantum dot of graphene nanoribbon qubit for Quantum information

“…In the dot region (where 0 ≤ y ≤ L) (2) and in the barrier region [19] (where y < 0 or y > L) (3) where ℏ is Planck's constant, is the Fermi velocity of graphene, ∂x, ∂y and ∂z are Pauli matrices, =±1 related to spin up and spin down, 2Δ is the gap induced by the substrate, 2…”

“…The exceptional electronic properties of graphene have ensured a rapid growth of interest as the base material for electronic circuitry [1]. Graphene-based quantum dot considers the best candidate for this device and can be implemented for quantum computers [2,3,4]. This computer works depending on superposition and entanglement phenomena [5,6], where the spin of electrons acts as a quantum bit (qubit) [7][8][9][10].…”

“…The electrons spin are coupled via exchange coupling and the coupling controlled by barrier voltage represented by low energy effective Hamiltonians: ℋ( )= 12 (t) 1 . 2 .…”

Symmetry and size effects on energy and entanglement of an exciton in coupled quantum dots

“…Moreover, they are very useful because of their potential applications not only in quantum device design, but also in the currently active field of quantum information processing. [4][5][6][7] It has been proposed that quantum bits (qubits) can be represented by either electron spin states [8][9][10] or exciton states. [11,12] Since the entanglement of qubits plays an important role in quantum communication and quantum computation, it is essential to study entanglement in these systems.…”