Ptychographic retrieval for complete ultrashort pulse amplitude swing reconstruction

Ultrafast experiments require precise temporal characterization of laser pulses, where pulse reconstruction is typically achieved through iterative retrieval algorithms. In this context, the amplitude swing technique has emerged as a robust and versatile tool for measuring scalar and vector pulses, using a compact inline setup. Here, we develop a unified theory of amplitude swing and introduce a ptychographic iterative engine algorithm to retrieve scalar and vector pulses from the different amplitude swing implementations (conventional and generalized). For scalar pulses, we show the new capability of retrieving both amplitude and phase. The algorithm is validated with simulated and experimental traces of scalar and vector pulses, which benefit from the new algorithm. In conclusion, a powerful tool for pulse characterization is provided, extending the capabilities of amplitude swing (e.g., to double pulses) and enhancing the ultrafast optics measurement toolkit.