Small third-order optical-nonlinearity detection free of laser parameters

Abstract

We demonstrate a novel, versatile method for sensitive measurement of nonresonant third-order optical nonlinearities in waveguides. The measurement is referenced to a bulk sample with well-known nonlinear optical properties, thus ruling out the influence of laser pulse parameters like duration, contrast, and spectral phase or amplitude. Since the generated mixing product is heterodyne detected, extremely small third-order optical nonlinearities, e.g., from air-filled short waveguides, can be measured.

Dispersion-modulation by high material loss in microstructured polymer optical fibers

“…Recently, n 2 was measured experimentally at λ=1550 nm in a PMMA bulk sample (which can be assumed to have the same n 2 value as a PMMA mPOF) to be approximately 1.9 times that of silica [15], using nearly degenerate FWM process combined with heterodyne technique and directly comparing the value of the PMMA to the value of fused silica bulk sample [16], so the estimate above for λ=1064 nm seems reasonable.…”

Dispersion of the nonlinear refractive index in photonic bandgap waveguides

“…The measurement is based on our recently reported ReBuS technique, where the nonlinear refractive index of the waveguide under test is measured by referencing its value to the nonlinearity of a bulk sample with wellknown nonlinear optical properties [2]. The experimental setup is similar to [2] using a mode-locked Er:fiber laser as a source and combining a nearly degenerate four-wave-mixing (FWM) configuration with a heterodyne detection scheme for sensitive measurement of the nonlinear refractive index phase 2 .…”

“…The experimental setup is similar to [2] using a mode-locked Er:fiber laser as a source and combining a nearly degenerate four-wave-mixing (FWM) configuration with a heterodyne detection scheme for sensitive measurement of the nonlinear refractive index phase 2 . Q…”