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We demonstrate how to generate arbitrary optical vector fields in the full C band (1535nm – 1570nm), with a new class of ultrafast wavefront shaper. A device capable of generating a sequence of arbitrary 2D spatial/polarization wavefronts at a bandwidth-limited rate of 4.4 THz.

Over the last decade, wavefront shaping techniques with spatial light modulators have enabled the control of coherent light through disordered systems, like biological tissues or multimode fibre that has suffered from scattering or mode mixing. Beyond spatial focusing of light on a single speckle grain, these techniques have been extended to the control of broadband light. Spatio-temporal focusing has been achieved, which corresponds to compensation for the pulse broadening in a single speckle grain [1]. The temporal control of light in all the spatial positions, including the full polarization control, has however not been achieved.

When coherent light propagates through a disordered system, such as white paint or biological tissue, its spatial properties are mixed and the resulting transmitted field forms a speckle pattern. Although the size of a speckle grain is diffraction-limited, this complex interference figure is detrimental for all conventional imaging systems. Over the last decade, wavefront shaping techniques have opened a new way to perform imaging through disordered systems using spatial light modulators (SLM), which offer millions of degrees of freedom to control light propagation. Notably, several techniques have demonstrated the capacity of using a thick scattering medium as a “perfect scattering lens” to arbitrary focus light after the medium in a given position, with a spot size limited by the size of the speckle grain, i.e. diffraction [1]. Among these techniques, the optical transmission matrix (TM) of the scattering medium can be easily measured [2], and contains the linear relation between the input fields and the output fields.