Related papers: Robust Quantum Memory in a Trapped-Ion Quantum Net…
We report the observation of entanglement between a single trapped atom and a single photon at a wavelength suitable for low-loss communication over large distances, thereby achieving a crucial step towards long range quantum networks. To…
The reversible transfer of the quantum information between a photon, an information carrier, and a quantum memory with high fidelity and reliability is the prerequisite for realizing a long-distance quantum communication and a quantum…
We use a co-trapped ion ($^{88}\mathrm{Sr}^{+}$) to sympathetically cool and measure the quantum state populations of a memory-qubit ion of a different atomic species ($^{40}\mathrm{Ca}^{+}$) in a cryogenic, surface-electrode ion trap. Due…
The so-called state-carving protocol generates high-fidelity entangled states at an atom-cavity interface without requiring high cavity cooperativity. However, this protocol is limited to 50\% efficiency, which restricts its applicability.…
A promising scheme for building scalable quantum simulators and computers is the synthesis of a scalable system using interconnected subsystems. A prerequisite for this approach is the ability to faithfully transfer quantum information…
We propose and analyze an optically loaded quantum memory exploiting capacitive coupling between self-assembled quantum dot molecules and electrically gated quantum dot molecules. The self-assembled dots are used for spin-photon…
Universal control of multiple qubits -- the ability to entangle qubits and to perform arbitrary individual qubit operations -- is a fundamental resource for quantum computation, simulation, and networking. Here, we implement a new…
Multiphoton entangled states are a key resource for quantum networks and measurement-based quantum computation. Scalable protocols for generating such states using solid-state spin-photon interfaces have recently emerged, but practical…
Qubits based on ions trapped in linear radio-frequency traps form a successful platform for quantum computing, due to their high fidelity of operations, all-to-all connectivity and degree of local control. In principle there is no…
We report on the implementation of quantum entanglement distribution and quantum state teleportation over a 14.4-km urban dark-fiber link, which is partially underground, partially overhead, and patched in several stations. We characterize…
Quantum memories for light are essential building blocks for quantum repeaters and quantum networks. Integrated operations of quantum memories could enable scalable application with low-power consumption. However, the photonic quantum…
Entangled photon pairs are a ubiquitous resource in quantum technologies, used in quantum key distribution and quantum networking as well as fundamental tests of non-locality. For scalable quantum networks, pairs that are indistinguishable…
We demonstrate ultrafast coherent coupling between an atomic qubit stored in a single trapped cadmium ion and a photonic qubit represented by two resolved frequencies of a photon. Such ultrafast coupling is crucial for entangling networks…
We demonstrate single-shot qubit readout with fidelity sufficient for fault-tolerant quantum computation, for two types of qubit stored in single trapped calcium ions. For an optical qubit stored in the (4S_1/2, 3D_5/2) levels of 40Ca+ we…
The high-fidelity storage of quantum information is crucial for quantum computation and communication. Many experimental platforms for these applications exhibit highly biased noise, with good resilience to spin depolarisation undermined by…
Efficient storage of telecom-band quantum optical information represents a crucial milestone for establishing distributed quantum optical networks. Erbium ions in crystalline hosts provide a promising platform for telecom quantum memories;…
We demonstrate long-lived coherence in internal hyperfine states of a single \Ca{43} trapped-ion qubit $[T_2=1.2(2)\s]$, and in external motional states of a single \Ca{40} trapped-ion qubit $[T_2'=0.18(4)\s]$, in the same apparatus. The…
Quantum repeater holds the promise for scalable long-distance quantum communication. Towards a first quantum repeater based on memory-photon entanglement, significant progresses have made in improving performances of the building blocks.…
High-precision optical phase stabilization in quantum networks is fundamentally constrained by the strict photon-flux and duty-cycle limits required to avoid disturbing fragile quantum states. This challenge becomes especially critical when…
Photon recoil is one of the fundamental limitations for high-fidelity control of trapped-atom qubits such as neutral atoms and trapped ions. In this work, we derive an analytical model for efficiently evaluating the motion-induced…