PT  - JOURNAL ARTICLE
AU  - Hu, Shuren
AU  - Khater, Marwan
AU  - Salas-Montiel, Rafael
AU  - Kratschmer, Ernst
AU  - Engelmann, Sebastian
AU  - Green, William M. J.
AU  - Weiss, Sharon M.
TI  - Experimental realization of deep-subwavelength confinement in dielectric optical resonators
AID  - 10.1126/sciadv.aat2355
DP  - 2018 Aug 01
TA  - Science Advances
PG  - eaat2355
VI  - 4
IP  - 8
4099  - http://advances.sciencemag.org/content/4/8/eaat2355.short
4100  - http://advances.sciencemag.org/content/4/8/eaat2355.full
SO  - Sci Adv2018 Aug 01; 4
AB  - The ability to highly localize light with strong electric field enhancement is critical for enabling higher-efficiency solar cells, light sources, and modulators. While deep-subwavelength modes can be realized with plasmonic resonators, large losses in these metal structures preclude most practical applications. We developed an alternative approach to achieving subwavelength localization of the electric and displacement fields that is not accompanied by inhibitive losses. We experimentally demonstrate a dielectric bowtie photonic crystal structure that supports mode volumes commensurate with plasmonic elements and quality factors that reveal ultralow losses. Our approach opens the door to the extremely strong light-matter interaction regime with, simultaneously incorporating both an ultralow mode volume and an ultrahigh quality factor, that had remained elusive in optical resonators.