collaborators

5 papers

physics.optics2026

Metasurfaces for neutral-atom trapping

Chengyu Fang, Minjeong Kim, Mark Saffman +2

Trapped neutral atoms are one of the leading platforms for quantum information technologies, in particular for quantum computing, but scaling them to array sizes needed for utility…

physics.optics2026

Silicon-on-sapphire metasurfaces generate arrays of dark and bright traps for neutral atoms

Chengyu Fang, Minjeong Kim, Hongyan Mei +10

We demonstrated crystalline silicon-on-sapphire (c-SOS) metasurfaces that convert a Gaussian beam into arrays of complex optical traps, including arrays of optical bottle beams tha…

physics.optics2025

All-passive upconversion of incoherent near-infrared light at intensities down to 10 W/cm

Rabeeya Hamid, Demeng Feng, Pournima Narayanan +10

Frequency upconversion, which converts low-energy photons into higher-energy ones, typically requires intense coherent illumination to drive nonlinear processes or the use of exter…

physics.optics2025

Preventing overfitting in infrared ellipsometry using temperature dependence: fused silica as a case study

Shenwei Yin, Jin-Woo Cho, Demeng Feng +6

Fitting oscillator models to variable-angle spectroscopic ellipsometry (VASE) data can lead to non-unique, unphysical results. We demonstrate using temperature-dependent trends to…

physics.optics2025

Broadband light extraction from near-surface NV centers using crystalline-silicon antennas

Minjeong Kim, Maryam Zahedian, Wenxin Wu +9

We use crystalline silicon (Si) antennas to efficiently extract broadband single-photon fluorescence from shallow nitrogen-vacancy (NV) centers in diamond into free space. Our desi…