6533b838fe1ef96bd12a3bbe
RESEARCH PRODUCT
Transfer of arbitrary two-qubit states via a spin chain
Tjg ApollaroFrancesco PlastinaSimone PaganelliSalvatore LorenzoG. M. PalmaG. M. Palmasubject
FOS: Physical sciencesSettore FIS/03 - Fisica Della MateriaMagnetizationsymbols.namesakeAtomic and Molecular PhysicsLattice (order)Quantum mechanicstwo-qubit statesQuantum informationQuantum information sciencespin chainPhysicsQuantum Physicsspin chain quantum state transfer quantum communicationquantum state transferSpin quantum numberAtomic and Molecular Physics and OpticsCondensed Matter - Other Condensed MatterQubitsymbolsand OpticsHamiltonian (quantum mechanics)Quantum Physics (quant-ph)Curse of dimensionalityOther Condensed Matter (cond-mat.other)description
We investigate the fidelity of the quantum state transfer (QST) of two qubits by means of an arbitrary spin-1/2 network, on a lattice of any dimensionality. Under the assumptions that the network Hamiltonian preserves the magnetization and that a fully polarized initial state is taken for the lattice, we obtain a general formula for the average fidelity of the two qubits QST, linking it to the one- and two-particle transfer amplitudes of the spin-excitations among the sites of the lattice. We then apply this formalism to a 1D spin chain with XX-Heisenberg type nearest-neighbour interactions adopting a protocol that is a generalization of the single qubit one proposed in Ref. [Phys. Rev. A 87, 062309 (2013)]. We find that a high-quality two qubit QST can be achieved provided one can control the local fields at sites near the sender and receiver. Under such conditions, we obtain an almost perfect transfer in a time that scales either linearly or, depending on the spin number, quadratically with the length of the chain.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-04-16 |