Optimized Design of the Lithium Niobate for Spectrally‐Pure‐State Generation at MIR Wavelengths Using Metaheuristic Algorithm

Abstract

Quantum light sources in the mid‐infrared (MIR) band play an important role in many applications, such as quantum sensing, quantum imaging, and quantum communication. However, there is still a lack of high‐quality quantum light sources in the MIR band, such as the spectrally pure single‐photon source. In this work, the generation of a spectrally‐pure state in an optimized poled lithium niobate crystal using a metaheuristic algorithm is presented. In particular, the particle swarm optimization algorithm is adopted to optimize the duty cycle of the poling period of the lithium niobate crystal. With this approach, the spectral purity can be improved from 0.820 to 0.998 under the third group‐velocity‐matched condition, and the wavelength‐tunable range from 3.0 to 4.0 µm for the degenerate case and 3.0 to 3.7 µm for the nondegenerate case. This work paves the way for developing quantum photonic technologies at the MIR wavelength band.

Mid-infrared spectrally-pure single-photon states generation from 22 nonlinear optical crystals

“…For the GVM 3 condition, the purity can be further improved from 0.82 to near 1 using the custom poling crystal scheme, for example by machine learning method or metaheuristic algorithm [25,86].…”

“…On the experimental side, PPLN [14][15][16], GaP [17], and silicon waveguide [18] have been investigated to prepare single-photon source; PPLN [19] has been studied for entangled photon source generation. On the theory side, PPLN [20], PPKN [21], PMN-0.38PT [22], etc have been investigated for single-photon source [23][24][25][26][27]; p-doped semiconductor [28] has been studied for entangled photon source. In addition, some studies explored single-photon detection by superconducting nanowire single-photon detector (SNSPD) [29][30][31] or by silicon avalanche photodiode (SAPD) in an up-conversion configuration [14,32].…”

Mid-infrared Spectrally Pure Single-Photon States Generation from 22 Nonlinear Optical Crystals

“…For the GVM 3 condition, the purity can be further improved from 0.82 to near 1 using the custom poling crystal scheme, for example, by applying the machine learning method or metaheuristic algorithm [25,89].…”

“…On the theory side, PPLN [20], periodically poled potassium niobate (PPKN) [21], 0.62Pb(Mg 1/3 Nb 2/3 )O 3 − 0.38PbTiO 3 (PMN-0.38PT) [22], etc. have been investigated for single-photon source [23][24][25][26][27]; p-doped semiconductor [28] has been studied for entangled photon source. In addition, some studies explored single-photon detection by superconducting nanowire single-photon detector (SNSPD) [29][30][31] or by silicon avalanche photodiode (SAPD) in an upconversion confguration [14,32].…”

Research Progress in Tunable Metamaterial Absorbers

“…Reasonable adjustment of various parameters of metamaterials has a crucial impact on the absorption performance of MAs. [ 90–94 ] The possibility of manipulating MAs absorption is provided by dynamically adjusting these parameters. Over the past decade, extensive research has been conducted to make passive MAs active (i.e., tunable or reconfigurable), enabling real‐time control of absorption in the required frequency band.…”