Xiu-Min Lin

Scalable, high-speed one-way quantum computer in coupled-cavity arrays

We propose an efficient method to realize a scalable, high-speed quantum computer in a two-dimensional (2D) array of coupled cavities, based on coherent displacements of an arbitrary state of cavity fields in a closed phase space. Because the nontrivial geometric phase shifts fast accumulate between the qubits in nearest-neighbor cavities, a large-scale 2D cluster state can be created within a short time. We discuss the feasibility of our method for scalable solid-state quantum computation.We propose an efficient method to realize a large-scale one-way quantum computer in a twodimensional (2D) array of coupled cavities, based on coherent displacements of an arbitrary state of cavity fields in a closed phase space. Due to the nontrivial geometric phase shifts accumulating only between the qubits in nearest-neighbor cavities, a large-scale 2D cluster state can be created within a short time. We discuss the feasibility of our method for scale solid-state quantum computation.

Strong photon blockade with intracavity electromagnetically induced transparency in a blockaded Rydberg ensemble

We consider the dynamics of intracavity electromagnetically induced transparency (EIT) in an ensemble of strongly interacting Rydberg atoms. By combining the advantage of variable cavity lifetimes with intracavity EIT and strongly interacting Rydberg dark-state polaritons, we show that such intracavity EIT system could exhibit very strong photon blockade effect.

Heralded quantum memory for single-photon polarization qubits

We propose a scheme to implement a heralded quantum memory for single-photon polarization qubits with a single atom trapped in an optical cavity. In this scheme, an injected photon only exchanges quantum state with the atom, so that the heralded storage can be achieved by detecting the output photon. We also demonstrate that the scheme can be used for realizing the heralded quantum state transfer, exchange, and entanglement distribution between distant nodes. The ability to detect whether the operation has succeeded or not is crucial for practical application.

Scheme for tunable quantum phase gate and effective preparation of graph-state entanglement

A scheme is presented for realizing a quantum phase gate with three-level atoms, solid-state qubits\char22{}often called artificial atoms, or ions that share a quantum data bus such as a single-mode field in the cavity quantum electrodynamics system or a collective vibrational state of trapped ions. In this scheme, the conditional phase shift is tunable and controllable via the total effective interaction time. Furthermore, the method can be used to effectively prepare graph states, which are important resources for quantum computation, quantum error correction, studies of multiparticle entanglement, and fundamental tests of nonlocality and decoherence.

Implementation of quantum controlled phase gate and preparation of multiparticle entanglement in cavity QED

Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom{fleld detuning.Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom—field detuning.Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom-field detuning.更多还原