Work

Structured coupling beam control of six-wave mixing: from Helical Ince-Gaussian to Laguerre-Gaussian modes

Year: 2026

Type: article

Abstract: We theoretically investigate six-wave mixing (SWM) in a coherently driven six-level atomic system using a structured coupling field. The probe and generated-field responses are obtained using the density-matrix formalism combined with the Maxwell Bloch equations. A Helical Ince–Gaussian (HIG) beam is introduced as the coupling field, and its ellipticity is varied to study the influence of its transverse structure on the nonlinear mixing process. In the zero ellipticity limit, the HIG modes reduce to the corresponding Laguerre–Gaussian (LG) modes. The effect of the LG modes is further examined for radial indices p = 0,1 and azimuthal indices l = 1,2. The normalized generated-field intensity increases with increasing l for both radial orders, whereas increasing p reduces the intensity due to the additional radial node and associated spatial redistribution of the coupling field. Among the modes considered, the LG mode (p,l) = (0,2) produces the largest response, with an approximately 1.06-fold enhancement over the Gaussian coupling case. These results demonstrate that the spatial structure of the coupling field provides an additional means of controlling higher-order nonlinear wave-mixing processes.

Source: Physica Scripta

DOI: 10.1088/1402-4896/aebf0b

Authors: Naincy Shrivastava, Mobassir Ahmad, Niladri Sarkar, Raghavan K Easwaran

Institution: Indian Institute of Technology Patna

Language: English

Topic: Quantum optics and atomic interactions

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: Indian Institute of Technology, Patna, Department of Science and Technology, Ministry of Science and Technology, India, Okinawa Institute of Science and Technology Graduate University

Award: G6627827262