ИСТИНА

High-peak power mid-infrared (mid-IR) and short-wavelength-infrared (SWIR) pulses with a pulse width τ0 close to the carrier field cycle T0 provide a powerful resource for ultrafast optical science and advanced photonic technologies [1]. Because the photon energy ħω0 of such T0-nigh SWIR/mid-IR pulses is below the band gap Eg of most of the technologically relevant solid-state semiconductor materials, these pulses, unlike their near-infrared counterparts, can drive and probe ultrafast electron dynamics not only near the surface, but also deep inside solid-state semiconductors, serving to set an unprecedentedly precise control over the fastest physical processes in solids [2] and helping induce and gate ultrafast electric-current transients in solids as a route toward petahertz optoelectronics [3]. In this work we have shown that soliton self-compression in a suitably designed gas-filled AR-guiding hollow-core fiber provides a source of ultrashort near-to-mid-IR field waveforms with a pulse energy up to 28 μJ, peak power up to 4 GW, and a pulse width smoothly tunable, via gas-pressure adjustment inside the gas-filled hollow fiber, all the way down to a single field cycle at ≤ 6.6 fs. With an active carrier–envelope phase (CEP) stabilization extended to its entire multioctave bandwidth, the single-cycle near-to-mid-IR fiber output is CEP-stable within 140 mrad and can be finely tailored toward a desired CEP profile. High-order harmonics generated by such field waveforms in solids exhibit clear signatures of a strong-field, nonperturbative impulsive response to a single-cycle optical driver. This research was supported by RSF Grants # 20-12-00088, # 22-12-00149 and RFBR Grant # 20-21-00131. [1] Balciunas, T.; Fourcade-Dutin, C.; Fan, G.; Witting, T.; Voronin, A. A.; Zheltikov, A. M.; Gerome, F.; Paulus, G. G.; Baltuska, A.; Benabid, F. A strong-field driver in the single-cycle regime based on self-compression in a kagome fibre. Nat. Commun. , 6, No. 6117, (2015). [2] Ghimire, S.; DiChiara, A. D.; Sistrunk, E.; Agostini, P.; DiMauro, L. F.; Reis, D. A. Observation of high-order harmonic generation in a bulk crystal. Nat. Phys. , 7, 138−141, (2011). [3] JSchiffrin, A.; Paasch-Colberg, T.; Karpowicz, N.; Apalkov, V.; Gerster, D.; Mühlbrandt, S.; Korbman, M.; Reichert, J.; Schultze, M.; Holzner, S.; Barth, J. V.; Kienberger, R.; Ernstorfer, R.; Yakovlev, V. S.; Stockman, M. I.; Krausz, F. Optical-field-induced current in dielectrics. Nature, 493, 70−74, (2013).