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Electrospray Deposition of Uniform Thickness Ge23Sb7S70 and As40S60 Chalcogenide Glass Films
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Mid-infrared nonlinear absorption in As2S3 chalcogenide glass
Optics Express
|November 10, 2016
Summary
Mid-infrared nonlinear absorption in arsenic trisulfide (As2S3) glasses is significantly stronger than previously thought. This intrinsic property, driven by two-photon excitation, impacts high-power fiber applications.
Area of Science:
- Materials Science
- Nonlinear Optics
- Photonics
Background:
- Arsenic trisulfide (As2S3) glasses are crucial for supercontinuum generation using high-power laser pulses.
- Understanding nonlinear optical properties is essential for optimizing fiber-based photonic devices.
Purpose of the Study:
- To investigate and quantify mid-infrared (MIR) nonlinear absorption in As2S3 glasses.
- To determine the origin and magnitude of this intrinsic nonlinear absorption mechanism.
Main Methods:
- Experimental measurement of nonlinear absorption in As2S3 glasses under MIR laser excitation.
- Analysis of two-photon excitation pathways and excited-state absorption.
Main Results:
- Observed MIR nonlinear absorption is 3-4 orders of magnitude stronger than near-infrared two-photon absorption in As2S3.
- This strong absorption is an intrinsic property of As2S3, not due to contaminants.
- At 100 kW peak power, MIR nonlinear absorption is comparable to background loss in As2S3 fibers.
- At 1 MW peak power, MIR nonlinear absorption exceeds background loss by ~2 orders of magnitude.
Conclusions:
- As2S3 exhibits exceptionally strong intrinsic MIR nonlinear absorption.
- This phenomenon significantly affects high-power light propagation in As2S3 fibers, impacting supercontinuum generation and device performance.
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