Photon-added coherent states and their quantum entanglement at a beam splitter

Gholamreza Honarasa, Alireza Bagheri, Abdolrasoul Gharaati

Berradaa

Gang Ren

K. Berrada, M. A. Al-Rajhi

Dmitry N. Makarov

The study of new quantum states and methods for their generation is an important part of the current development of quantum technologies. One of the most important characteristics of such states is their quantum entanglement. Photon-added coherent states, which are defined as $${\text{|}}\alpha ,n\rangle = {{\mathcal{N}}_{n}}{{({{\hat {a}}^{\dag }})}^{n}}{\text{|}}\alpha \rangle $$ , where $${{\mathcal{N}}_{n}}$$ is the normalization constant, $${\text{|}}\alpha \rangle $$ is the coherent state, $${{\hat {a}}^{\dag }}$$ is the creation operator, and n is the number of added photons, have been introduced relatively recently. The quantum entanglement of such states passing through a beam splitter has been considered for the first time in this work. A simple analytical representation of the wavefunction at the outputs of the beam splitter has been found and the quantum entanglement of the resulting two-qubit states has been considered. It has been shown that new quantum states have good prospects for their use in quantum technologies.

Hadiah Bint Monir, Shahid Iqbal

Beam splitter mediated entanglement of nonlinear photon-added coherent states was studied by Honarasa, Bagheri and Gharaati [1]. We believe that this work contains errors in numerical computations of linear entropy and Mandel parameter which lead to wrong conclusions. We point out the possible errors and describe the necessary corrections. The conclusions based on our arguments are in complete agreement with previously published literature.