Generation of Isolated Attosecond Pulses with 20 to 28 Femtosecond Lasers

TLDR

Isolated attosecond pulses are powerful tools for exploring electron dynamics in matter, yet until now they have only been produced with high‑power, few‑cycle lasers that are difficult to construct and operate. The authors aim to develop a method that generates isolated attosecond pulses using 20‑fs lasers from a hollow‑core fiber and 28‑fs lasers directly from an amplifier. They employ generalized double optical gating with these multicycle laser pulses to produce the attosecond bursts. The pulses, generated in argon gas, have durations of 260 as and 148 as, and the relaxed laser‑pulse‑duration requirement makes attophysics accessible to many laboratories.

Abstract

Isolated attosecond pulses are powerful tools for exploring electron dynamics in matter. So far, such extreme ultraviolet pulses have only been generated using high power, few-cycle lasers, which are very difficult to construct and operate. We propose and demonstrate a technique called generalized double optical gating for generating isolated attosecond pulses with 20 fs lasers from a hollow-core fiber and 28 fs lasers directly from an amplifier. These pulses, generated from argon gas, are measured to be 260 and 148 as by reconstructing the streaked photoelectron spectrograms. This scheme, with a relaxed requirement on laser pulse duration, makes attophysics more accessible to many laboratories that are capable of producing such multicycle laser pulses.