Nanophotonics Research Program
AMOLF is a pioneer in the research field of Nanophotonics: the science of controlling light at scales smaller than the wavelength. Using metallic and dielectric nanostructures that are sculpted in 2D and 3D architectures, researchers are able to control the flow and confinement of light, in ways not accessible in conventional geometries. Nanophotonics is not just concerned with light, but also with the material excitations that light interacts with: phonons, electrons, spins and excitons.
The research program includes:
1) Hybrid nanophotonic matter for emitters, excitons and spins
Nanophotonics and nano-photovoltaics researchers join forces to efficiently address the reaction of matter with light. Researchers have developed various strategies for this purpose, such as dielectric cavities that store photons for a very long time period and plasmonics that use metals to confine light to small volumes. Hybrid nanophotonics plays a crucial role in the simultaneous management of light and charge in structures with plasmonic and dielectric resonances in solid state lighting and in nanophotovoltaic structures. Our current research further explores light in extreme confinement for plasmonic chemistry, and strong coupling of light, molecular vibrations and polaritons in nanometer scale cavities.
2) Coupling light and motion in optomechanical metamaterials
The radiation pressure of light in nanoscale resonators can be so strong that it drives mechanical vibrations of MHz-GHz acoustic resonators. Researchers are developing optomechanical resonators with unprecedented photon-phonon coupling strengths. Beyond single units, the researchers also target opto-mechanical metamaterials, such as extended arrays of coupled opto-mechanical unit cells, which allow to build non-reciprocal as well as topological materials for light and sound.
3) New computing paradims enabled by light
A research line founded in 2017 explores cavity-exciton systems to control exciton gain and nonlinearities in arrays of microcavities. Ultimately, this research aims to deliver classical and quantum Ising simulators, in which exponentially hard computational problems as well as outstanding problems in condensed matter physics are solved by light. In a parallel development we study ‘metasurfaces’ as analog computation and processing devices that act on incident optical wavefronts. We are pursuing linear, nonlinear, and active metasurfaces, and envision applications in analog computation, sensing and metrology.
4) Fundamental limits on shaping light, and its energy, noise and information content
Optical functions are constrained by material linearity, passivity and reciprocity, and at a fundamental level by causality and thermodynamics. The metasurface field brought to optics the notion of inverse-problem based design: for any function a prescribed nanophotonic geometry that performs it can be found. Researchers are exploring the consequences for optimal design of scatterers, metasurfaces and resonators for nanophotovoltaics, wavefront re-shaping for lighting, microscopy and optical signal processing.
5) Advanced instrumentation and materials
AMOLF has a strong track record in developing near-field microscopy, nanomanipulation, ultrafast spectroscopy, cathodoluminescence (i.e. nanoscopy using electron beam excitation) and momentum-space imaging, which accesses radiation patterns of single nano-objects. Researchers are working towards picosecond cathodoluminescence microscopy
Figure: Stillness rules the eye of a hurricane; without a hurricane no eye, and without an eye no hurricane. In a similar manner, physicists of research institute AMOLF, the University of Amsterdam and the University of Texas at Austin, have captured light in the eye of an optical vortex.