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Ultrafast Coherent Absorption in Diamond Metamaterials
Artemios Karvounis1, Venkatram Nalla2, Kevin F MacDonald1
1Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Southampton, SO17 1BJ, UK.
Advanced Materials (Deerfield Beach, Fla.)
|February 28, 2018
Summary
Researchers demonstrate diamond metasurfaces for ultrafast optical modulation. This nanostructured diamond enables light-by-light control of few-optical-cycle pulses, offering a new platform for photonic metamaterials.
Area of Science:
- Photonics
- Materials Science
- Metamaterials
Background:
- Coherent control of absorption enables high-contrast all-optical gating.
- Response speed is limited by the spectral width of the absorption line.
- Planar, subwavelength-thickness materials are key for this mechanism.
Purpose of the Study:
- To introduce diamond as a material platform for visible/near-infrared photonic metamaterials.
- To experimentally demonstrate coherent light-by-light modulation using nanostructured diamond.
- To explore diamond's potential for ultrafast optical switching.
Main Methods:
- Fabrication of a nanostructured polycrystalline diamond metasurface (170 nm thick).
- Utilizing focused ion beam milling for structuring a free-standing diamond membrane.
- Experimental demonstration of coherent modulation with few-optical-cycle (6 fs) pulses.
Main Results:
- Achieved coherent light-by-light modulation with nanostructured diamond.
- Demonstrated strong, spectrally near-flat absorption across a wide visible to near-infrared range.
- Showcased diamond's capability for modulating ultrashort optical pulses.
Conclusions:
- Diamond is a viable material for visible/near-infrared photonic metamaterials.
- Nanostructured diamond metasurfaces facilitate ultrafast all-optical modulation.
- Diamond offers advantages over plasmonic metals for broadband coherent control.
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