Robust and ultralow-energy-threshold ignition of lean fuels by an ultrashort-pulsed laser

Laser ignition (LI) is a promising electrode-less alternative to electronic spark ignition of lean fuel/air mixtures, offering high thermal efficiency with low harmful emissions. One of the most widely adopted LI methods is nanosecond laser-induced spark ignition (ns-LISI), in which combustible mixtures undergo multiphoton ionization followed by avalanche breakdown, resulting in high-temperature and high-pressure plasma along with shockwaves. However, inevitable shot-to-shot energy fluctuations ...