Description
High-order transverse-mode lasers are important tools for a wide range of emerging applications, motivating continued efforts toward simple and flexible control of structured laser fields. Recently, we have developed a general approach for arbitrary high-order mode generation based on cavity-symmetry control and selective mode excitation. By deliberately introducing intracavity astigmatism, the transverse symmetry of the resonator is broken and its eigenmodes are restricted, substantially enhancing the controllability and purity of high-order transverse modes. Combined with simple off-axis pumping, this approach enables efficient generation of two-dimensional Hermite–Gaussian (HG) modes with independently and continuously tunable mode indices. Subsequent astigmatic mode conversion produces Laguerre–Gaussian (LG) vortex beams with independently tunable radial and azimuthal indices. The accessible modes therefore span the full Hermite–Laguerre–Gaussian spatial-mode space, greatly extending the degrees of freedom available for intracavity structured-light control. Experimentally, two-dimensional modes beyond HG$_{200,200}$` and one-dimensional modes beyond HG$_{1500,0}$, as well as their LG counterparts, have been demonstrated, while the restriction of cavity eigenmodes enables high modal purity even at extremely high orders.
| I am the presenting author | No |
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| If you are not the presenting author, please give the presenting author's name: | Quan Sheng |