We propose a practical solid-state system capable of demonstrating quantum teleportation. The setup exploits recent advances in the optical control of excitons in coupled quantum dots, in order to produce maximally entangled Bell and Greenberger-Horne-Zeilinger states. Only two unitary transformations are then required: a quantum controlled- $\mathrm{NOT}$ gate and a Hadamard gate. The laser pulses necessary to generate the maximally entangled states, and the corresponding unitary transformations, are given explicitly.We propose a practical solid-state system capable of demonstrating quantum teleportation. The setup exploits recent advances in the optical control of excitons in coupled quantum dots, in order to produce maximally entangled Bell and Greenberger-Horne-Zeilinger states. Only two unitary transformations are then required: a quantum controlled-$\mathrm{NOT}$ gate and a Hadamard gate. The laser pulses necessary to generate the maximally entangled states, and the corresponding unitary transformations, are given explicitly.

arXiv:cond-mat/9906034Physical Review ADec 8, 200030 citations

Quantum Theory of the Solid State

Elsevier eBooksJan 1, 1991295 citations

Quantum Theory of the Solid State

Elsevier eBooksJan 1, 1974264 citations

Mott physics in the half-filled Hubbard model on a family of vortex-full square lattices

Dominik Ixert, Fakher F. Assaad, Kai Phillip Schmidt

We study the half-filled Hubbard model on a one-parameter family of vortex-full square lattices ranging from the isotropic case to weakly coupled Hubbard dimers. The ground-state phase diagram consists of four phases: A semimetal and a band insulator which are connected to the weak-coupling limit, and a magnetically ordered N\'eel phase and a valence bond solid (VBS) which are linked to the strong-coupling Mott limit. The phase diagram is obtained by quantum Monte Carlo (QMC) and continuous unitary transformations (CUTs). The CUT is performed in a two-step process: Nonperturbative graph-based CUTs are used in the Mott insulating phase to integrate out charge fluctuations. The resulting effective spin model is tackled by perturbative CUTs about the isolated dimer limit yielding the breakdown of the VBS by triplon condensation. We find three scenarios when varying the interaction for a fixed anisotropy of hopping amplitudes: (i) one direct phase transition from N\'eel to semimetal, (ii) two phase transitions VBS to N\'eel and N\'eel to semimetal, or (iii) a smooth crossover from VBS to the band insulator. Our results are consistent with the absence of spin-liquid phases in the whole phase diagram.We study the half-filled Hubbard model on a one-parameter family of vortex-full square lattices ranging from the isotropic case to weakly coupled Hubbard dimers. The ground-state phase diagram consists of four phases: A semimetal and a band insulator which are connected to the weak-coupling limit, and a magnetically ordered N\'eel phase and a valence bond solid (VBS) which are linked to the strong-coupling Mott limit. The phase diagram is obtained by quantum Monte Carlo (QMC) and continuous unitary transformations (CUTs). The CUT is performed in a two-step process: Nonperturbative graph-based CUTs are used in the Mott insulating phase to integrate out charge fluctuations. The resulting effective spin model is tackled by perturbative CUTs about the isolated dimer limit yielding the breakdown of the VBS by triplon condensation. We find three scenarios when varying the interaction for a fixed anisotropy of hopping amplitudes: (i) one direct phase transition from N\'eel to semimetal, (ii) two phase transitions VBS to N\'eel and N\'eel to semimetal, or (iii) a smooth crossover from VBS to the band insulator. Our results are consistent with the absence of spin-liquid phases in the whole phase diagram.

arXiv:1408.0022Physical Review BNov 18, 201421 citations

Quantum Theory of the Solid State

Elsevier eBooksJan 1, 1974152 citations

\mathrm{NOT}

gate and a Hadamard gate. The laser pulses necessary to generate the maximally entangled states, and the corresponding unitary transformations, are given explicitly.