Low-threshold supercontinuum generation in highly nonlinear chalcogenide nanowires

Abstract

We demonstrate low-threshold supercontinuum generated in a highly nonlinear arsenic selenide chalcogenide nanowire with tailored dispersion. The tapered submicrometer chalcogenide fiber exhibits an ultrahigh nonlinearity, n(2) approximately 1.1x10(-17) m(2)/W and an effective mode area of 0.48 mum(2), yielding an effective nonlinearity of gamma approximately 93.4 W/m, which is over 80,000 times larger than standard silica single-mode fiber at a wavelength of approximately 1550 nm. This high nonlinearity, in conjunction with the engineered anomalous dispersion, enables low-threshold soliton fission leading to large spectral broadening at a dramatically reduced peak power of several watts, corresponding to picojoule energy.

Temporal solitons and pulse compression in photonic crystal waveguides

“…In addition to the aforementioned dispersion engineering, additional research has centered on reducing the required intensity of chip-scale nonlinear effects via material engineering. Semiconductors [11,17], chalcogenides [18][19][20], tellurites [21], and doped silica [22], have Kerr coefficients that are typically at least two orders of magnitude larger than silica fiber, further reducing the required energy threshold in integrated structures. In summary, the highly confined optical modes in dispersion-engineered semiconductor PhCWGs offer a long awaited development of low-intensity threshold nonlinearities to compliment the wellestablished large dispersion of periodic media [12-14, 23, 24].…”

Nonlinear Optics in Doped Silica Glass Integrated Waveguide Structures

“…On the other hand, the obtained value is more than 200 times larger, due to the much smaller effective mode area of the doped silica waveguide in c o n t r a s t t o t h e w e a k l y g u i d e d s i n g l e m o d e f i b e r . H o w e v e r , s e m i c o n d u c t o r s a n d chalcogenides nanotapers definitely have the upper hand in terms of bulk nonlinear parameter values, where ~ 200,000 W -1 km -1 have been reported Yeom et al, 2008), due to both the smaller effective mode areas and the larger n 2 , as previously mentioned. From Eq.…”

Nonlinear optics at low powers: Alternative mechanism of on-chip optical frequency comb generation

“…where we assumed the two resonators to be identical, each with the roundtrip time T c = L/v g , circumference L, nonlinearity γ and the TPA r coefficients; φ 1(2) , τ 1(2) , and κ 1 (2) are defined the same way as before.…”

“…Two strategies have been traditionally used to enhance nonlinear optical effects: (1) targeting materials with high optical nonlinearities, such as chalcogenide glasses [1,2], silicon [3,4], AlGaAs [5,6], and (2) employing resonant structures to increase local field intensity. The choice of material is oftentimes dictated by fabrication limitations and the overall design compatibility requirements.…”