Fig. 4: High-harmonic random walks in OAM space.
From: Non-cascade random walks in solid-state high harmonic generation
a Simulated and b experimental non-cascade random walks generated by high-harmonic processes in a bulk crystal of α-quartz. c Flat-top distribution of the third-step high-harmonic random walk (blue), compared to those from classical (orange) and quantum (pink) walks. d Diffused distribution of the fourth-step high-harmonic random walk (blue), compared to those from classical (orange) and quantum (pink) walks.
