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arXiv · 1503.07665

Two-dimensional materials and the coherent control of nonlinear optical interactions

Shraddha M. Rao·Ashley Lyons·Thomas Roger·Matteo Clerici·Nikolay I. Zheludev·Daniele Faccio
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Abstract

Deeply sub-wavelength two-dimensional films may exhibit extraordinarily strong nonlinear effects. Here we show that 2D films exhibit the remarkable property of a phase-controllable nonlinearity, i.e., the amplitude of the nonlinear polarisation wave in the medium can be controlled via the pump beam phase and determines whether a probe beam will "feel" or not the nonlinearity. This is in stark contrast to bulk nonlinearites where propagation in the medium averages out any such phase dependence. We perform a series of experiments in graphene that highlight some of the consequences of the optical nonlinearity phase-dependence, {such as} the coherent control of nonlinearly diffracted beams, single-pump-beam {induced} phase-conjugation and the demonstration of a nonlinear mirror characterised by negative reflection. The observed phase sensitivity is not specific to graphene but rather is solely a result of the dimensionality and is therefore expected in all 2D materials.

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Shraddha M. Rao, Ashley Lyons, Thomas Roger, Matteo Clerici, Nikolay I. Zheludev, Daniele Faccio. 2015-03-26. Two-dimensional materials and the coherent control of nonlinear optical interactions. https://arxiv.org/abs/1503.07665

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