Researcher:
Ali, Farhan

Profile Picture
ORCID

Job Title

PhD Student

First Name

Farhan

Last Name

Ali

Name

Name Variants

Ali, Farhan

Email Address

Birth Date

Filters

20211

Advanced Search

Filter by

Settings

Researcher Of Publications: search.filters.isAuthorOfPublication.80793a90-2ad0-486d-ba35-51e9ad958b69

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    PublicationOpen Access
    A hybrid broadband metalens operating at ultraviolet frequencies
    (Nature Publishing Group (NPG), 2021) Department of Physics; Ali, Farhan; Ramazanoğlu, Serap Aksu; Faculty Member; Department of Physics; Graduate School of Sciences and Engineering; College of Sciences; N/A; 243745
    The investigation on metalenses have been rapidly developing, aiming to bring compact optical devices with superior properties to the market. Realizing miniature optics at the UV frequency range in particular has been challenging as the available transparent materials have limited range of dielectric constants. In this work we introduce a low absorption loss and low refractive index dielectric material magnesium oxide, MgO, as an ideal candidate for metalenses operating at UV frequencies. We theoretically investigate metalens designs capable of efficient focusing over a broad UV frequency range (200–400 nm). The presented metalenses are composed of sub-wavelength MgO nanoblocks, and characterized according to the geometric Pancharatnam–Berry phase method using FDTD method. The presented broadband metalenses can focus the incident UV light on tight focal spots (182 nm) with high numerical aperture (NA ≈ 0.8). The polarization conversion efficiency of the metalens unit cell and focusing efficiency of the total metalens are calculated to be as high as 94%, the best value reported in UV range so far. In addition, the metalens unit cell can be hybridized to enable lensing at multiple polarization states. The presented highly efficient MgO metalenses can play a vital role in the development of UV nanophotonic systems and could pave the way towards the world of miniaturization.