arXiv subjects

Ba An Nguyen

Publications and source records attributed to Ba An Nguyen.

5 recordsLinked to original sources

arXiv2021

Towards effective shaping of large-amplitude high-fidelity Schrodinger cat states by inefficient photon number resolving detection

We propose an efficient way to generate optical analogs of both even and odd Schrodinger cat states (SCSs) with high fidelity, large amplitude and reasonable generation rate. The resource consumed are a single-mode squeezed vacuum state (SMSV) and possibly a single photon or nothing. We report the generation of even (odd) SCS with amplitude 4.2, fidelity higher than 0.99 and reasonable generation rate by subtraction of 30(31) photons from SMSV by ideal photon number detection. In the case of inefficient detectors, maintaining SCS size and its fidelity at the same level as in the case of ideal detectors results in a dramatic decrease in the success probability. In order to have certain harmony between the three characteristics (large amplitude, high fidelity and acceptable success probability for the generation scheme) in the case of imperfect detection, highly transmitting beam splitters should not be used and number of the subtracted photons must be reduced to 10(11).

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arXiv2004

Multi-dimensional trio coherent states

We introduce a novel class of higher-order, three-mode states called K-dimensional trio coherent states. We study their mathematical properties and prove that they form a complete set in a truncated Fock space. We also study their physical content by explicitly showing that they exhibit nonclassical features such as oscillatory number distribution, sub-poissonian statistics, Cauchy-Schwarz inequality violation and phase-space quantum interferences. Finally, we propose an experimental scheme to realize the state with K=2 in the quantized vibronic motion of a trapped ion.

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arXiv2004

Hillery-type squeezing in fan-states

We study the Hillery-type, i.e. $N$-th power, amplitude squeezing in the fan-state $| ξ;2k,f>_{F}$ characterized by $ξ\in \mathcal{C}$, $k=1,2,3,...$ and $f$ a nonlinear operator-valued function. We show that for a given $k$ there exists a critical $ξ_c$ such that for $0<|ξ|\leq|ξ_c|$ squeezing occurs simultaneously in $2k$ directions for the powers $N$ which are a multiple of $2k$. This result does not depend on the concrete form of $f$, i.e. it holds true for both $f\equiv 1$ and $f\neq 1$. However, for $f\neq 1$, which is realized here in the ion trap context, the squeezing directions as well as the magnitude of $ξ$ can be controlled by adjusting the system driving parameters.

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arXiv2003

Improved scheme for generation of vibrational trio coherent states of a trapped ion

We improve a previously proposed scheme (Phys. Rev. A 66 (2002) 065401) for generating vibrational trio coherent states of a trapped ion. The improved version is shown to gain a double advantage: (i) it uses only five, instead of eight, lasers and (ii) the generation process can be made remarkably faster.

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arXiv2003

Multimode cat-state entanglement and network teleportation

Schemes for generation and protocols for network teleportation of multimode entangled cat-states are proposed. Explicit expressions for probability of successful teleportation are derived for both symmetric and asymmetric networks.

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