Related papers: Resonant two-laser spin-state spectroscopy of a ne…
Solid-state spins are promising as interfaces from stationary qubits to single photons for quantum communication technologies. Semiconductor quantum dots have excellent optical coherence, exhibit near unity collection efficiencies when…
The spin states of electrons and holes confined in InAs quantum dot molecules have recently come to fore as a promising system for the storage or manipulation of quantum information. We describe here a feasible scheme for complete quantum…
The spin of an electron in a self-assembled InAs/GaAs quantum dot molecule is optically prepared and measured through the trion triplet states. A longitudinal magnetic field is used to tune two of the trion states into resonance, forming a…
We demonstrate all optical electron spin initialization, storage and readout in a single self-assembled InGaAs quantum dot. Using a single dot charge storage device we monitor the relaxation of a single electron over long timescales…
We investigate site-controlled In$_{0.25}$Ga$_{0.75}$As quantum dots in (111)B GaAs pyramidal recesses as spin qubits. Combining scanning confocal cryomicroscopy, magneto-photoluminescence studies and resonant excitation, we identify and…
Coherent interactions between spins in quantum dots are a key requirement for quantum gates. We have performed pump-probe experiments in which pulsed lasers emitting at different photon energies manipulate two distinct subsets of electron…
Combining highly coherent spin control with efficient light-matter coupling offers great opportunities for quantum communication and networks, as well as quantum computing. Optically active semiconductor quantum dots have unparalleled…
A spin-photon interface should operate with both coherent photons and a coherent spin to enable cluster-state generation and entanglement distribution. In high-quality devices, self-assembled GaAs quantum dots are near-perfect emitters of…
Semiconductor quantum dots (known as artificial atoms) hold great promise for solid-state quantum networks and quantum computers. To realize a quantum network, it is crucial to achieve light-matter entanglement and coherent quantum-state…
Quantum state transfer from flying photons to stationary matter qubits is an important element in the realization of quantum networks. Self-assembled semiconductor quantum dots provide a promising solid-state platform hosting both single…
We present a theory of the optical control of the spin of an electron in an InAs quantum dot. We show how two Raman-detuned laser pulses can be used to obtain arbitrary single-qubit rotations via the excitation of an intermediate trion…
We demonstrate coherent optical control of a single hole spin confined to an InAs/GaAs quantum dot. A superposition of hole spin states is created by fast (10-100 ps) dissociation of a spin-polarized electron-hole pair. Full control of the…
We employ ultrafast pump-probe spectroscopy with photocurrent readout to directly probe the dynamics of a single hole spin in a single, electrically tunable self-assembled quantum dot molecule formed by vertically stacking InGaAs quantum…
We propose an experiment to observe coherent oscillations in a single quantum dot with the oscillations driven by spin-orbit interaction. This is achieved without spin-polarised leads, and relies on changing the strength of the spin-orbit…
We present a scheme for efficient state teleportation and entanglement swapping using a single quantum-dot spin in an optical microcavity based on giant circular birefringence. State teleportation or entanglement swapping is heralded by the…
Two-electron charged self-assembled quantum dot molecules exhibit a decoherence-avoiding singlet-triplet qubit subspace and an efficient spin-photon interface. Here, we demonstrate that the cycling transitions originating from auxiliary…
Magneto photoluminescence and excitation spectroscopy are used to probe the excited state spectrum of negatively charged trions in a InGaAs quantum dot. A single dot optical charging device allows us to selectively prepare specific few (1e,…
The electron spin state of a singly charged semiconductor quantum dot has been shown to form a suitable single qubit for quantum computing architectures with fast gate times. A key challenge in realizing a useful quantum dot quantum…
A method is proposed for the optical rotation of the spin of an electron in a quantum dot using excited trion states to implement operations up to two orders of magnitude faster than those of most existing proposals. Key ingredients are the…
The Zeeman-split spin-states of a single electron confined in a self-assembled quantum dot provide an optically-accessible spin qubit. For III-V materials the nuclear spins of the solid-state host provide an intrinsic noise source,…