Related papers: Single calcium-40 ion as quantum memory for photon…
In quantum information and communication, optical schemes provide simple and intuitive experimental implementations. Of particular importance is quantum state preparation. In this thesis, the creation of polarisation entanglement using a…
We interface a spontaneous parametric down conversion (SPDC) crystal and a cold atomic ensemble and demonstrate a highly efficient quantum memory through polarization-encoded single-photon qubits. Specifically, narrowband heralded single…
Multi-photon entangled states play a crucial role in quantum information applications such as secure quantum communication, scalable computation, and high-precision quantum metrology. Quantum memory for entangled states is a key component…
Single-photon sources based on semiconductor quantum dots find several applications in quantum information processing due to their high single-photon indistinguishability, on-demand generation, and low multiphoton emission. In this context,…
We propose a scheme that utilizes the collective enhancement of a photonic mode inside an atomic ensemble together with a proper Zeeman manifold in order to achieve a heralded polarization entangled Bell state. The entanglement is between…
We present the implementation of a programmable atom-photon quantum interface, employing a single trapped $^{40}$Ca$^+$ ion and single photons. Depending on its mode of operation, the interface serves as a bi-directional atom-photon…
Bulk diamond phonons have been shown to be a versatile platform for the generation, storage, and manipulation of high-bandwidth quantum states of light. Here we demonstrate a diamond quantum memory that stores, and releases on demand, an…
Quantum memories are key components in quantum information networks. Their ability to store and retrieve information on demand makes repeat-until-success strategies scalable. Warm alkali-metal vapours are interesting candidates for the…
Quantum entanglement of particles is regarded as a fundamental character in quantum information, in which quantum state should be given for whole system instead of independently describing single particle. Constructing quantum memory of…
In quantum teleportation, the state of a single quantum system is disembodied into classical information and purely quantum correlations, to be later reconstructed onto a second system that has never directly interacted with the first one.…
Quantum repeaters are critical components for distributing entanglement over long distances in presence of unavoidable optical losses during transmission. Stimulated by Duan-Lukin-Cirac-Zoller protocol, many improved quantum-repeater…
We report on experiments demonstrating the reversible mapping of heralded single photons to long lived collective optical atomic excitations stored in a Pr$^{3+}$:Y$_2$SiO$_5$ crystal. A cavity-enhanced spontaneous down-conversion source is…
Photon-based quantum information processing promises new technologies including optical quantum computing, quantum cryptography, and distributed quantum networks. Polarization-encoded photons at telecommunication wavelengths provide a…
We propose a linear optical scheme for the teleportation of unknown ionic states, the entanglement concentration for nonmaximally entangled states for ions via entanglement swapping and the remote preparation for ionic entangled states. The…
We report on the quantum storage and retrieval of photonic polarization quantum bits onto and out of a solid state storage device. The qubits are implemented with weak coherent states at the single photon level, and are stored for 500 ns in…
We propose a scheme for long-distance quantum communication where the elementary entanglement is generated through two-photon interference and quantum swapping is performed through one-photon interference. Local "polarization" maximally…
The faithful storage of a quantum bit of light is essential for long-distance quantum communication, quantum networking and distributed quantum computing. The required optical quantum memory must, first, be able to receive and recreate the…
The full control of single photons is important in quantum information and quantum networking. A convenient storage device for photons is the key to memory assisted quantum communication and computing. While even a simple optical fiber can…
In the fluorescence light of a single atom, the probability for emission of a photon with certain polarization depends on the polarization of the photon emitted immediately before it. Here correlations of such kind are investigated with a…
We design an effect protocol for protecting the single-photon entanglement from photon loss and decoherence. The protocol only requires some auxiliary single photons and the linear optical elements. By operating the protocol, the photon…