Dual-chirped optical parametric amplification of high-energy single-cycle laser pulses

We demonstrate how a scheme called advanced dual-chirped optical parametric amplification (DC-OPA) that employs two kinds of nonlinear crystal (BiB3O6 and MgO-doped lithium niobate) can generate high-energy, single-cycle mid-infrared laser pulses. In experiments, the advanced DC-OPA scheme achieved carrier-to-envelope phase-stable mid-infrared laser pulses with a bandwidth of over one octave (1.4-3.1 mu m) and an output pulse energy of 53 mJ. The pulse duration was compressed to 8.58 fs, which corresponds to 1.05 cycles with a central wavelength of 2.44 mu m and a peak power of 6 TW. To our knowledge, the obtained values for the pulse energy and peak power are the highest achieved for optical parametric amplification of single-cycle mid-infrared laser pulses. Moreover, owing to the energy scalability of the advanced DC-OPA scheme, the prospects of the multi-terawatt sub-cycle laser pulses are discussed. A new form of chirped amplification with two different nonlinear crystals can generate high-energy, single-cycle laser pulses with terawatt-level peak powers.