Publications by Type: Journal Article

Giovanna Palermo, Andrew Lininger, Alexa Guglielmelli, Loredana Ricciardi, Giuseppe Nicoletta, Antonio De Luca, Joon-Suh Park, Soon Wei Daniel Lim, Maryna L. Meretska, Federico Capasso, and Giuseppe Strangi. 10/10/2022. “All-Optical Tunability of Metalenses Permeated with Liquid Crystals.” ACS Nano, 16, 10, Pp. 16539–16548. Publisher's Version acsnano.2c05887.pdf
Soon Wei Daniel Lim, Maryna L Meretska, and Federico Capasso. 10/11/2021. “A High Aspect Ratio Inverse-Designed Holey Metalens.” Nano Letters, 21, 20, Pp. 8642–8649. Publisher's VersionAbstract
Free-standing nanofins or pillar meta-atoms are the most common constituent building blocks in metalenses and metasurfaces in general. Here, we present an alternative metasurface geometry based on high aspect ratio via-holes. We design and characterize metalenses comprising ultradeep via-holes in 5 μm thick free-standing silicon membranes with hole aspect ratios approaching 30:1. These metalenses focus incident infrared light into a diffraction-limited spot. Instead of shaping the metasurface optical phase profile alone, we engineer both transmitted phase and amplitude profiles simultaneously by inverse-designing the lens effective index profile. This approach improves the impedance match between the incident and transmitted waves, thereby increasing the focusing efficiency. The holey platform increases the accessible aspect ratio of optical nanostructures without sacrificing mechanical robustness. The high nanostructure aspect ratio also increases the chromatic group delay range attainable, paving the way for a generation of high aspect ratio ruggedized flat optics, including large-area broadband achromatic metalenses.
Soon Wei Daniel Lim, Joon-Suh Park, Maryna L. Meretska, Ahmed H. Dorrah, and Federico Capasso. 7/7/2021. “Engineering phase and polarization singularity sheets.” Nature Communications, 12, 1, Pp. 4190. Publisher's VersionAbstract
Optical phase singularities are zeros of a scalar light field. The most systematically studied class of singular fields is vortices: beams with helical wavefronts and a linear (1D) singularity along the optical axis. Beyond these common and stable 1D topologies, we show that a broader family of zero-dimensional (point) and two-dimensional (sheet) singularities can be engineered. We realize sheet singularities by maximizing the field phase gradient at the desired positions. These sheets, owning to their precise alignment requirements, would otherwise only be observed in rare scenarios with high symmetry. Furthermore, by applying an analogous procedure to the full vectorial electric field, we can engineer paraxial transverse polarization singularity sheets. As validation, we experimentally realize phase and polarization singularity sheets with heart-shaped cross-sections using metasurfaces. Singularity engineering of the dark enables new degrees of freedom for light-matter interaction and can inspire similar field topologies beyond optics, from electron beams to acoustics.
Shaoliang Yu, Jinsheng Lu, Vincent Ginis, Simon Kheifets, Soon Wei Daniel Lim, Min Qiu, Tian Gu, Juejun Hu, and Federico Capasso. 3/12/2021. “On-chip optical tweezers based on freeform optics.” Optica, 8, 3, Pp. 409. Publisher's Version 2021_yu_et_al._optica.pdf
Meixin Shen, Soon Wei Daniel Lim, Eugene S. Tan, Hazel H. Oon, and Ee Chee Ren. 8/31/2019. “HLA Correlations with Clinical Phenotypes and Risk of Metabolic Comorbidities in Singapore Chinese Psoriasis Patients.” Molecular Diagnosis & Therapy, 23, 6, Pp. 751–760. Publisher's VersionAbstract
Introduction: Psoriasis is a systemic, chronic inflammatory disease that not only afflicts the skin but is also associated with cardiovascular disease and metabolic syndrome. The strongest susceptibility loci for the disease is within the human leukocyte antigen (HLA) complex, though specific HLA allelic associations vary between populations. Objective: Our objective was to investigate HLA associations with clinical phenotypes of psoriasis and metabolic syndrome in Chinese psoriasis cases. Methods: We conducted an observational case–control study in Singapore with a cohort of psoriasis cases consecutively recruited from an outpatient specialist dermatological center (n = 120) compared with 130 healthy controls. Results: Significant HLA associations with psoriasis were observed with HLA-A*02:07, B*46:01, C*01:02, and C*06:02. The three-locus haplotype of A*02:07-C*01:02-B*46:01 was also significant (odds ratio [OR] 3.07; p = 9.47 × 10−5). We also observed an association between nail psoriasis and HLA-A*02:07 carriers (OR 4.50; p = 0.002), whereas C*06:02 carriers were less prone to have nail involvement (OR 0.16; p = 0.004). HLA-A*02:07 was also identified as a possible risk allele for hypertension (OR 2.90; p < 0.05), and C*01:02 was a possible risk allele for dyslipidemia (OR 3.36; p < 0.05), both known to be common comorbidities in patients with psoriasis. Conclusion: Our results demonstrate the growing importance of discerning population-specific clinical phenotypes and their association with certain HLA alleles in psoriasis.
Aaron Zhenghui Thong, Soon Wei Daniel Lim, Aniq Ahsan, Glen Tai Wei Goh, Jianwei Xu, and Jia Min Chin. 2014. “Non-close-packed pore arrays through one-step breath figure self-assembly and reversal.” Chemical Science, 5, 4, Pp. 1375–1382. Publisher's Version c3sc52258j.pdf