On-chip Electrical Soliton Oscillators for Picosecond Pulse Self- Generation and THz Electronics.

摘要

Solitons are pulsed waves exhibiting unique nonlinear properties. In electronics domain, electrical solitons had been passively produced by using nonlinear transmission lines. Prior to this proposal, our group built, for the first time, an active electrical circuit in a discrete platform, which robustly self-generated a stable, periodic train of electrical solitons. This was achieved by combining a nonlinear transmission line with a specially designed amplifier in a circular topology. The goal of this proposal was to build upon the demonstrated concept and to develop electrical soliton oscillators in integrated forms with improved speed, e.g., with the pulse duration into the picosecond regime. Pursuing this goal, we have developed: (1) integrated CMOS soliton oscillators of the circular topology with a pulse width of 293 ps and a repetition period down to 530 ps; (2) proof-of-concept discrete soliton oscillators with a new, reflective topology with a pulse width of 445 ps and repetition time of 9.7 ns (duty cycle of only 4.6%); (3) integrated GaAs mode- locked oscillators of the reflection topology with a pulse width of 16 ps and repetition time of 53 ps; (4) proof-of-concept discrete soliton-based chaos oscillators; and (5) a phase-noise theory of distributed oscillators including soliton/pulsed oscillators.