Phase-controlled transistor action by cascading of second-order nonlinearities in KTP

Abstract

We demonstrate a 4.6-to-1 modulation depth imposed on the fluence of an intense 1.06-microm picosecond pulse by varying the relative phase of a weak second-harmonic control pulse under near phase-matched conditions. This transistorlike action is based on quadratic nonlinearities in KTP.

Third-order nonlinearity of graphene: Effects of phenomenological relaxation and finite temperature

“…The nonlinear susceptibility of graphene [4] is both strong-per atom it is orders of magnitude higher than that of common gapped semiconductors and metals-and controllable by the chemical potential [5,6], which can be tuned by an external gate voltage [7,8] or chemical doping [9]. With the possibilities it offers for integration in siliconbased optical integrated circuits, graphene is an exciting new candidate for enhancing nonlinear optical functionalities in silicon-based on-chip optical devices, such as on-chip broadband light sources, electro-optic modulators [10,11], optical switches [12][13][14], and optical transistors [15,16]. In realizing some of these devices [14], the presence of second-order optical nonlinearities, especially second harmonic generation (SHG), is a key requirement.…”

Control of nonlinear absorption and amplification of light in Er^3+-doped fluoroindate glass

“…For example, the interaction between two beams can be demonstrated in laserinduced grating experiments, such as in Kerr-like media 4 and in photorefractive materials, 5 and in cross-phasemodulation experiments. 6,7 Another important category of process is based on the effects of induced absorption or amplification owing to the coupling between two beams. Examples of this category are illustrated in Refs.…”

Quadratic Cascading: Effects and Applications

“…results in an intensity controlled transistor. 46 The FF throughput, despite the use of temporal pulses with a Gaussian beam distribution, clearly exhibits a modulation versus input relative phase, with a contrast as high as 4.6:1 when employing SH pulses with energy 1.2% of the pump at 1.064µm. Notice that, although KTP is Type II phase-matched for SHG at this wavelength, the FF input was injected at 45° with respect to ordinary and extraordinary crystal directions, thereby resulting in standard Type I cascading.…”

“…21,[45][46] For a fixed input FF intensity, a variation in the relative phase between the SH seed and the FF pump induces a shift in the overall phase matching response, as seen in Fig. 4.…”

“…Finally, it is worth mentioning the possibilities offered by Type II and SH-seeded guided-wave interactions, in analogy to the plane-wave cases discussed above. 21,[40][41][42][45][46] Wavelength Shifter. If one of the two processes involved in cascading is made non-degenerate in frequency, a small frequency shift can be obtained at the expense of a FF input pump through the cascaded interaction: (17) as demonstrated in bulk BBO by Tan et al ., 76 and proposed in a MQW waveguide with a vertical SH resonator by Gorbounova et al 77 and in a QPM lithium niobate channel by Gallo et al 78 This configuration for wavelength shifting offers a large 3dB bandwith and amplification at the expense of the input pump, which can be within the useful spectral range of the Er-doped fiber amplifiers used in telecommunications.…”