Publications by Hao Song | EPFL Graph Search

Space-time wave packets with reduced divergence and tunable group velocity generated in free space after multi-mode fiber propagation

Tobias Kippenberg, Maxim Karpov, Hao Song, Xinzhou Su

Previously, space-time wave packets (STWPs) have been gen-erated in free space with reduced diffraction and a tunable group velocity by combining multiple frequency comb lines each carrying a single Bessel mode with a unique wave num-ber. It might be poten ...

Optica Publishing Group2023

Generation of OAM-carrying space-time wave packets with time-dependent beam radii using a coherent combination of multiple LG modes on multiple frequencies

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

Space-time (ST) wave packets, in which spatial and temporal characteristics are coupled, have gained attention due to their unique propagation characteristics, such as propagation invariance and tunable group velocity in addition to their potential ability ...

Optica Publishing Group2022

Experimental demonstration of dynamic spatiotemporal structured beams that simultaneously exhibit two orbital angular momenta by combining multiple frequency lines, each carrying multiple Laguerre-Gaussian modes

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

In general, there are different, relatively independent forms of orbital angular momenta at a given propagation distance, which might exhibit different dynamic spatial characteristics. One type involves a beam with a helical phase-front that rotates around ...

Optica Publishing Group2022

Tunability of space-time wave packet carrying tunable and dynamically changing OAM value

Tobias Kippenberg, Maxim Karpov, Hao Song, Xinzhou Su

Space-time (ST) wave packets have gained much interest due to their dynamic optical properties. Such wave packets can be generated by synthesizing frequency comb lines, each having multiple complex-weighted spatial modes, to carry dynamically changing orbi ...

Optica Publishing Group2022

Synthesis of near-diffraction-free orbital-angular-momentum space-time wave packets having a controllable group velocity using a frequency comb

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

Novel forms of light beams carrying orbital angular momentum (OAM) have recently gained interest, especially due to some of their intriguing propagation features. Here, we experimentally demonstrate the generation of near-diffraction-free two-dimensional ( ...

Optica Publishing Group2022