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A low-loss suspended core As38Se62 fiber with core diameter of 4.5 μm and a zero-dispersion wavelength of 3.5 μm was used for mid-infrared supercontinuum generation. The dispersion of the fiber was measured from 2.9 to 4.2 μm and was in good correspondence with the calculated dispersion. An optical parametric amplifier delivering 320 fs pulses with a peak power of 14.8 kW at a repetition rate of 21 MHz was used to pump 18 cm of suspended core fiber at different wavelengths from 3.3 to 4.7 μm. By pumping at 4.4 μm with a peak power of 5.2 kW coupled to the fiber a supercontinuum spanning from 1.7 to 7.5 μm with an average output power of 15.6 mW and an average power >5.0 μm of 4.7 mW was obtained.

We present a novel CMOS-compatible fabrication technique for convex micro-nano lens arrays (MNLAs) with high packing density on the wafer scale. By means of conformal chemical vapor deposition (CVD) of hydrogenated amorphous silicon (a-Si:H) following patterning of silicon pillars via electron beam lithography (EBL) and plasma etching, large areas of a close packed silicon lens array with the diameter from a few micrometers down to a few hundred nanometers was fabricated. The resulting structure shows excellent surface roughness and high uniformity. The optical focusing properties of the lenses at infrared wavelengths were verified by experimental measurements and numerical simulation. This approach provides a feasible solution for fabricating silicon MNLAs compatible for next generation large scale, miniaturized optical imaging detectors and related optical devices.

Pan Ma acknowledges the financial support from the China Scholarship Council for her joint PhD Scholarship No. 201206020094. Yi Yu acknowledges the financial support from the China Scholarship Council for her PhD Scholarship No.201206110048. This research was conducted by the Australian Research Council (ARC) Centre of Excellence for Ultrahigh Bandwidth Devices for Optical Systems (project number CE110001018). Dr. Zhiyong Yang is supported by ARC DECRA project DE120101036 and Dr. Duk-Yong Choi by ARC Future Fellowship FT110100853. Dr. Xin Gai is supported by Discovery project DP130100086. Device fabrication was supported by the ANU node of the Australian National Fabrication Facility (ANFF).

We have designed and fabricated a 2-D photonic crystal hetero-structure cavity in the chalcogenide glass Ge(11.5)As(24)Se(64.5) that is fully embedded in a cladding with refractive index of 1.44. The low index contrast of this structure (≈1.21) means that high-Q resonances cannot be obtained using standard hetero-structure cavity designs based on W1 waveguides. We show that reducing the waveguide width can substantially improve light confinement, leading to high-Q resonances in a hetero-structure cavity. Numerical simulations indicate intrinsic Q(v)10(7) are possible with this approach. Experimentally, an optical cavity with a high intrinsic Q(v)7.6 x 10(5) was achieved in a structure with a theoretical Q(v) = 1.7 x 10(6).

We have fabricated 630 × 500 nm nanowires from Ge(11.5)As(24)Se(64.5) chalcogenide glass by electron beam lithography (EBL) and inductively coupled plasma (ICP) etching. The loss of the nanowire was measured to be 2.6 dB/cm for the fundamental TM mode. The nonlinear coefficient (γ) was determined to be ≈136 ± 7 W(-1)m(-1) at 1550 nm by both CW four-wave-mixing (FWM) and modeling. Supercontinuum (SC) was produced in an 18 mm long nanowire pumped by 1 ps pulses with peak power of 25 W.

We report first observation of net-gain from an optical parametric amplifier in a planar waveguide. This was achieved in a low-loss As(2)S(3) planar waveguide, with a strong nonlinearity (gamma approximately 10 /W/m) and tailored anomalous dispersion yielding efficient Raman-assisted four-wave mixing at telecom wavelengths. The experiments were in good agreement with theory, and indicate a peak net-gain greater than +16 dB for the signal and idler (+30 dB neglecting coupling losses) and a broad bandwidth spanning 180 nm.

Three-photon absorption (3PA) has been observed as the dominant mechanism for nonlinear absorption in wide-bandgap hydrogenated amorphous silicon (a-Si:H-W) at 1.55 μm. The nonlinear index n2 and 3PA coefficient were measured to be 22 × 10(-17)m(2)/W and 5.0 × 10(-26) m(3)/W(2) respectively at 1.55 μm by using the z-scan method. This indicates that the figure of merit (FOM) of this material is intensity dependent. A value FOM>60 is predicted at intensities below 0.5 GW/cm(2) which is the maximum practical intensity for high-bit-rate (>160 GB/s) alloptical signal processing. The nonlinear phase change in a-Si:H-W has been compared with other common nonlinear materials (c-Si, As(2)S(3), Ge(11.5)As(24)Se(64.5)) for a 2 cm long waveguide with a-Si:H-W showing the greatest potential for integrated devices for all-optical processing with a high nonlinear index and negligible nonlinear absorption at intensities < 0.5 GW/cm(2).

We show that highly nonlinear chalcogenide glass nanowire waveguides with near-zero anomalous dispersion should be capable of generating correlated photon-pairs by spontaneous four-wave mixing at frequencies detuned by over 17 THz from the pump where Raman noise is absent. In this region we predict a photon pair correlation of100, a figure of merit10 and brightness of ~8×10(8) pairs/s over a bandwidth of15 THz in nanowires with group velocity dispersion of5 ps∙km(-1) nm(-1). We present designs for double-clad Ge(11.5)As(24)Se(64.5) glass nanowires with realistic tolerance to fabrication errors that achieve near-zero anomalous dispersion at a 1420 nm pump wavelength. This structure has a fabrication tolerance of 80-170 nm in the waveguide width and utilizes a SiO(2)/Al(2)O(3) layer deposited by atomic layer deposition to compensate the fabrication errors in the film thickness.

We review the fabrication processes and properties of waveguides that have been made from chalcogenide glasses including highly nonlinear waveguides developed for all-optical processing.

We have fabricated 630 × 500 nm nanowires from Ge(11.5)As(24)Se(64.5) chalcogenide glass by electron beam lithography (EBL) and inductively coupled plasma (ICP) etching. The loss of the nanowire was measured to be 2.6 dB/cm for the fundamental TM mode. The nonlinear coefficient (γ) was determined to be ≈136 ± 7 W(-1)m(-1) at 1550 nm by both CW four-wave-mixing (FWM) and modeling. Supercontinuum (SC) was produced in an 18 mm long nanowire pumped by 1 ps pulses with peak power of 25 W.