Record-small photonic crystal based on a van der Waals material
CIC nanoGUNE Seminars
- Speaker
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Javier Alfaro, Nanooptics Group
- When
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2018/09/10
13:00 - Place
- nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian
- Add to calendar
-
iCal
Periodically patterned dielectrics -photonic crystals- provide opportunities
to shape and control the flow of light. However, they are not suitable for
deeply subwavelength scale applications, since the size of their unit cell is
comparable to the wavelength of light. We overcome this difficulty by
engineering a nanoscale hole array in a slab of a van der Waals material
(hexagonal boron nitride, h-BN) supporting ultra-confined phonon-polaritons
-atomic lattice vibrations coupled to electromagnetic fields. Such a hole
array represents a phonon-polaritonic crystal. We demonstrate both
theoretically and experimentally that the h-BN hole array presents angle- and
polarization-independent sharp Bragg resonances. Our results could be used for
the design of novel tunable infrared narrow-band couplers, absorbers and
thermal emitters based on van der Waals materials.