Related papers: Deterministic generation of a four-qubit W state u…
We propose a simple scheme for expanding a polarization-entangled W state. By mixing a single photon and one of the photons in an n-photon W state at a polarization-dependent beam splitter (PDBS), we can obtain an (n+1)-photon W state after…
We show how to make event-ready multi-partite entanglement between qubits which may be encoded on photons or matter systems. Entangled states of matter systems, which can also act as single photon sources, can be generated using the…
We generate and study the entanglement properties of novel states composed of three polarisation-encoded photonic qubits. By varying a single experimental parameter we can coherently move from a fully separable state to a maximally robust W…
We present a scheme for obtaining entangled photons and quantum phase gates in a room-temperature four-state tripod-type atomic system with two-mode active Raman gain (ARG). We analyze the linear and nonlinear optical response of this ARG…
We theoretically investigate polarization-entangled photon generation by using a semiconductor quantum dot embedded in a microcavity. The entangled states can be produced by the application of two cross-circularly polarized laser fields.…
We show how an entangled cluster state encoded in the polarization of single photons can be straightforwardly expanded by deterministically entangling additional qubits encoded in the path degree of freedom of the constituent photons. This…
Aiming the construction of quantum computers and quantum communication systems based on optical devices, in this work we present possible implementations of quantum and classical CNOTs gates, as well an optical setup for generation and…
We propose and work out a scheme to generate the entangled W states for a chain of N four-level atoms which are transported through an optical cavity by means of an optical lattice. This scheme is based on the combined laser-cavity mediated…
Two photons in free space pass each other undisturbed. This is ideal for the faithful transmission of information, but prohibits an interaction between the photons as required for a plethora of applications in optical quantum information…
Quantum gates are the essential block for quantum computer. High-dimensional quantum gates exhibit remarkable advantages over their two-dimensional counterparts for some quantum information processing tasks. Here we present a family of…
We propose the implementation of a light source, which can deterministically generate a rich variety of multi-mode quantum states. The desired states are encoded in the collective population of different ground hyperfine states of an atomic…
Entangling photons is a critical challenge for photonic quantum information processing: entanglement is a crucial resource for quantum communication and computation but can only be performed in a probabilistic manner when using linear…
An ideal controlled-NOT gate followed by projective measurements can be used to identify specific Bell states of its two input qubits. When the input qubits are each members of independent Bell states, these projective measurements can be…
We propose an optical scheme to generate genuine entangled states of four atomic qubits in optical cavities using a single-photon source, beam splitters and single photon detectors. We show how to generate deterministically sixteen…
In this paper, we give two very simple schemes to produce two kinds of W states, one kind is path W state with one photon and the other is multiphoton photon polarization W state. These schemes just need a common commercial multiport fiber…
We propose a method to generate a two-dimensional cluster state of polarization encoded photonic qubits from two coupled quantum dot emitters. We combine the recent proposal [N. H. Lindner and T. Rudolph, Phys. Rev. Lett. 103, 113602…
We describe a scheme that allows for the generation of any desired N-photon state on demand. Under ideal conditions, this requires only N single photon sources, laser pulses and linear optics elements. First, the sources should be…
We consider single photon realization of generalized N-qubit perfect W-states which are suitable for perfect teleportation and superdense coding. We propose schemes to generate generalized N-mode single photon perfect W-states and derive…
We propose a method to generate arbitrary symmetric states of N qubits, which can be easily associated with their entanglement classes. It is particularly suited to quantum optics systems like trapped ions or superconducting circuits. We…
The four-qubit states $\lvert\chi^{ij}\rangle$, exhibiting genuinely multi-partite entanglement have been shown to have many interesting properties and have been suggested for novel applications in quantum information processing. In this…