title: Adiabatic compression of quadratic temporal solitons in aperiodic quasi-phase-matching gratings.
abstract: We numerically show that it is possible to achieve adiabatic compression of femtosecond quadratic solitons in aperiodically poled lithium niobate device. Two-colored solitons of the fundamental wavelength of 1560 nm can be adiabatically shaped by using group-velocity matching schemes available in quasi-phase-matching (QPM) devices. We investigate the performance of the adiabatic compression based on two different group-velocity matching schemes: type-I (e: o + o) collinear QPM geometry and type-0 (e: e + e) non-collinear QPM geometry. Two-colored temporal solitons with pulse duration of 35 fs are generated without visible pedestals from 100-fs fundamental pulse. We also show that walking solitons with shorter pulse durations are adiabatically excited under small group-velocity mismatch condition. The walking solitons experience deceleration or acceleration during compression, depending on the sign of the groupvelocity- mismatch. The demonstrated adiabatic pulse shaping is useful for generation of shorter pulses with clean temporal profiles, efficient femtosecond second harmonic generation and group-velocity control.
authors.forename: Xianglong
authors.initials: X
authors.lastname: Zeng
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ashihara
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Fujioka
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Shimura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kuroda