Abstract
Optical vortices, which carry orbital angular momentum, offer special capabilities in a host of applications. A single-laser source with dual-beam-mode output may open up new research fields of nonlinear optics and quantum optics. We demonstrate a dual-channel scheme to generate femtosecond, dual-wavelength, and dual-beam-mode tunable signals in the near infrared wavelength range. Dual-wavelength operation is derived by stimulating two adjacent periods of a periodically poled lithium niobate crystal. Pumped by an Yb-doped fiber laser with a Gaussian (lp = 0) beam, two tunable signal emissions with different beam modes are observed simultaneously. Although one of the emissions can be tuned from 1520 to 1613 nm with the Gaussian (ls = 0) beam, the other is capable of producing a vortex spatial profile with different vortex orders (ls = 0 to 2) tunable from 1490 to 1549 nm. The proposed system provides unprecedented freedom and will be an exciting platform for super-resolution imaging, nonlinear optics, multidimensional quantum entanglement, etc.
Highlights
Optical vortices, which carry orbital angular momentum, offer special capabilities in a host of applications
The unique phase distribution can be described by an azimuthal phase dependence expðilαÞ, where l being an integer is known as the topological charge of the beam and α is the azimuthal angle.[1,2]
Previous efforts have focused on the transfer of the orbital angular momentum (OAM) in Optical parametric oscillators (OPOs) from the pump to the output beams
Summary
Optical vortices, which carry orbital angular momentum, offer special capabilities in a host of applications. The OAM of the pump vortex beam can be selectively transferred to one of the generated waves (signal or idler beam) by controlling the cavity losses.[10] owing to the vortex nature of the pump beam and the lower nonlinear gain (compared to the Gaussian pump), the output power is Downloaded From: https://www.spiedigitallibrary.org/journals/Advanced-Photonics on 31 Dec 2021 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
