Scientists now create ultrashort laser pulses with durations in femtoseconds or less, making them the shortest events ever produced. This technology has revolutionized science, aiding our understanding of atomic and molecular dynamics, advancing biomedical and industrial applications, and diagnostics. However, single pulses excite all resonances within their broad bandwidth, making it hard to target specific resonances.

To overcome this, scientists generate and amplify hundreds of ultrashort pulses with tightly spaced temporal intervals, creating high terahertz repetition rate bursts. Controlling these bursts allows selective excitation of desired optical frequencies, enhancing light-matter interactions and opening up various applications in fields like biomedical diagnostics and process analysis.