Radwanul Hasan Siddique

Samsung Semiconductor Inc · Image Sensor Lab

We introduce laser interference lithography (LIL) as a tool to fabricate hierarchical photonic nanostructures inspired by blue Morpho butterflies. For that, we utilize the interference pattern in vertical direction in addition to the conventional horizontal one. The vertical interference creates the lamellae by exploiting the back reflection from t...

The glasswing butterfly (Greta oto) has, as its name suggests, transparent wings with remarkable low haze and reflectance over the whole visible spectral range even for large view angles of 80°. This omnidirectional anti-reflection behaviour is caused by small nanopillars covering the transparent regions of its wings. In difference to other anti-re...

The wings of the black butterfly, Pachliopta aristolochiae, are covered by micro- and nanostructured scales that harvest sunlight over a wide spectral and angular range. Considering that these properties are particularly attractive for photovoltaic applications, we analyze the contribution of these micro- and nanostructures, focusing on the structu...

Numerous living organisms possess biophotonic nanostructures that provide colouration and other diverse functions for survival. While such structures have been actively studied and replicated in the laboratory, it remains unclear whether they can be used for biomedical applications. Here, we show a transparent photonic nanostructure inspired by the...

Aluminum (Al)-based nanoantennae traditionally suffer from weak plasmonic performance in the visible range, necessitating the application of more expensive noble metal substrates for rapidly expanding biosensing opportunities. We introduce a metasurface comprising Al nanoantennae of nanodisks-in-cavities that generate hybrid multipolar lossless pla...

Bioinspired Nanostructures How can glasswing butterflies make contact lenses more functional? In article number 2205113, Radwanul Hasan Siddique, Hyuck Choo, and co‐workers have shown that integrating glasswing butterfly wing‐inspired nanostructures on a scleral lens can enhance visibility, block UV radiation, reduce bacterial infection and add sen...

The generation of high-purity localized trions, dynamic exciton–trion interconversion, and their spatial modulation in 2D semiconductors are building blocks for the realization of trion-based optoelectronic devices. Here, we present a method for the alloptical control of the exciton-to-trion conversion process and its spatial distributions in a MoS...

Augmenting contact lenses with sensing capabilities requires incorporating multiple functionalities within a diminutive device. Inspired by multifunctional biophotonic nanostructures of glasswing butterflies, a nanostructured scleral lens with enhanced optical, bactericidal, and sensing capabilities is reported. When used in conjunction with a smar...

Landau damping has previously been shown to be the dominant nonlocal effect in sub-10nm plasmonic nanostructures, although its effects on the performance of plasmonic nanocavities are still poorly understood. In this work, the effects of Landau damping in sub-10-nm planar plasmonic nanocavities are analyzed theoretically, and it is shown that while...

The self-assembly of poly(dimethylsiloxane)-b-poly(trimethylene carbonate) (PDMS-b-PTMC) bottlebrush block polymers was investigated under different processing conditions. Small-angle X-ray scattering (SAXS) and UV/Visible spectroscopy provided insight into the self-assembly and structure in response to heating and applied pressure. In the absence...

Biomimicry is the practice of imitating naturally occurring bio‐designs through engineering and invention. For instance, Blue Morpho butterfly wing colors are a result of the reflection and refraction of nanostructures embedded in the wing and have inspired practical applications in nanofabrication and photonics. Interdisciplinary science education...

The wings of butterflies and moths (Lepidoptera) are typically covered with thousands of flat, overlapping scales that endow the wings with colorful patterns. Yet, numerous species of Lepidoptera have evolved highly transparent wings, which often possess scales of altered morphology and reduced size, and the presence of membrane surface nanostructu...

The spontaneous phase separation of two or more polymers is a thermodynamic process that can take place in both biological and synthetic materials and which results in the structuring of the matter from the micro- to the nanoscale. For photonic applications, it allows forming quasi-periodic or disordered assemblies of light scatterers at high throu...

Glaucoma, one of the leading cause of irreversible blindness, is largely caused by an elevated intraocular pressure (IOP). However, current IOP monitoring techniques inherit major disadvantages such as imprecision, no real or long time monitoring, and difficult readout. Here, we report on a highly miniaturized (200 um thick) optomechanical nanophot...

The utility of Fabry-Pérot based optical sensors is limited by their poor readout angle. We numerically demonstrate that adding bioinspired short-range-order nanostructuring to these devices leads to angle-independent Fano resonances, enabling wide angle optical sensing.

Numerous species of Lepidoptera have transparent wings, which often possess scales of altered morphology and reduced size, and the presence of membrane surface nanostructures that dramatically reduce reflection. Optical properties and anti-reflective nanostructures have been characterized for several clearwing Lepidoptera, but the developmental bas...

Numerous species of Lepidoptera have transparent wings, which often possess scales of altered morphology and reduced size, and the presence of membrane surface nanostructures that dramatically reduce reflection. Optical properties and anti-reflective nanostructures have been characterized for several ‘clearwing’ Lepidoptera, but the developmental b...

Enhancement of optical emission on plasmonic nanostructures is intrinsically limited by the distance between the emitter and nanostructure surface, owing to a tightly-confined and exponentially-decaying electromagnetic field. This fundamental limitation prevents efficient application of plasmonic fluorescence enhancement for diversely-sized molecul...

Enhancement of optical emission on plasmonic nanostructures is intrinsically limited by the distance between the emitter and nanostructure surface, owing to a tightly-confined and exponentially-decaying electromagnetic field. This fundamental limitation prevents efficient application of plasmonic fluorescence enhancement for diversely-sized molecul...

Flexible surface-enhanced Raman scattering (SERS) has received attention as a means to move SERS-based broadband biosensing from bench to bedside. However, traditional flexible periodic nano-arrangements with sharp plasmonic resonances or their random counterparts with spatially varying uncontrollable enhancements are not reliable for practical bro...

Aluminum metasurfaces with multipolar resonances are developed for brighter, broadband and multiplexed biosensing.

Recent works on metal-insulator-metal-based plasmonic antennas have shown that emitters could couple with higher-order gap-plasmon modes in sub-10-nm gaps to overcome quenching. However, these gaps are often physically inaccessible for functionalization and are not scalably manufacturable. Here, using a simple biomimetic batch-fabrication, a plasmo...

While numerous multifunctional antifouling nanostructures on insect wings have been previously studied and replicated, their potential incorporation into implantable medical devices remains unexplored. We have demonstrated the use of multifunctional bioinspired nanostructured membrane inspired by transparent butterfly wings for intraocular pressure...

A Raman-mode constraining-based implantable glucose sensor has been developed. Placed in the anterior chamber of the eye, the implanted sensor emits surface-enhanced Raman signal of mercaptophenylboronic acid molecules where the Raman-peak position indicates the ambient glucose concentration.

Diabetes mellitus is a chronic disease, and its management focuses on monitoring and lowering a patient’s glucose level to prevent further complications. By tracking the glucose-induced shift in the surface-enhanced Raman-scattering (SERS) emission of mercaptophenylboronic acid (MPBA), we have demonstrated fast and continuous glucose sensing in the...

Over the last couple of years, photonic materials with tailored -i.e. with deliberately introduced- structural disorder have attracted considerable interest in photovoltaics due to their extended spectral and angular range of effectiveness [1]. Notably, quasi-random nanostructures realized by e-beam lithography (EBL) have been integrated in solar c...

Colour produced by wavelength-dependent light scattering is a key component of visual communication in nature and acts particularly strongly in visual signalling by structurally-coloured animals during courtship. Two miniature peacock spiders (Maratus robinsoni and M. chrysomelas) court females using tiny structured scales (~ 40 × 10 μm2) that refl...

Subwavelength metal-dielectric plasmonic metasurfaces enable light management beyond the diffraction limit. However, a cost-effective and reliable fabrication method for such structures remains a major challenge hindering their full exploitation. Here, we propose a simple yet powerful manufacturing route for plasmonic metasurfaces based on a bottom...

A horn-shaped metal-clad InGaAsP nano-cavity with sloped sidewalls is proposed as a platform for nanoscale light sources. The nano-cavity’s physical dimensions are 350 × 350 × 350 nm^3, and its mode volume is 0.5 (λ_0/n)^3. In our numerical simulations and quantitative analysis, we have shown that the sloped sidewalls reduce metallic absorption and...

Inspired by the white beetle of the genus Cyphochilus, we fabricate ultra-thin, porous PMMA films by foaming with CO_2 saturation. Optimising pore diameter and fraction in terms of broad-band reflectance results in very thin films with exceptional whiteness. Already films with 60 µm-thick scattering layer feature a whiteness with a reflectance of 9...

Inspired by the hair of blue tarantulas, B.-K. Hsiung and co-workers made a highly periodic structural-colored material that shows consistent color from all viewing directions in article number 1600599. This finding overturns the conventional wisdom that non-iridescent color cannot be produced by long-range order photonic structures, opening new po...

The butterfly genus Hypolimnas features iridescent blue colouration in some areas of its dorsal wings. Here, we analyse the mechanisms responsible for such colouration on the dorsal wings of Hypolimnas salmacis and experimentally demonstrate that the lower thin lamina in the white cover scales causes the blue iridescence. This outcome contradicts o...

The butterfly genus Hypolimnas features iridescent blue colouration in some areas of its dorsal wings. Here, we analyse the mechanisms responsible for such colouration on the dorsal wings of Hypolimnas salmacis and experimentally demonstrate that the lower thin lamina in the white cover scales causes the blue iridescence. This outcome contradicts o...

Photonic structures with long-range order are inherently iridescent, suggesting by current theory. Contrary to this para- digm and inspired by biological photonic structures from hairs of blue tarantulas, a noniridescent photonic structure with long-range order is shown here. This photonic structure is hierarchical and has high degrees of rotationa...

We study numerically and experimentally the light harvesting properties of Pachliopta aristolochiae black wings consisting of disordered nano-holes assemblies surrounded by micrometre-spaced ridges. Broadband and omnidirectional anti-reflection properties are evidenced and originate from different light propagation regimes through the hierarchical...

Since the 20th century, scientists have been controlling and manipulating light with artificial photonic materials in order to devise new optical applications. However, millions of years of evolution in the biological world has developed their own photonic structures in the form of vivid ‘structural color’. For a long time, studies focusing on phot...

The interest of exploiting controlled disorder for absorption enhancement, e.g in perturbed photonic crystals, scattering layers or in bio-inspired light collection structures, will be discussed on the basis of simulation and experimental results.

Coupled with recent interest in economical, reliable renewable energy, a new research field has blossomed, that of bio-inspired nanostructures for light management in optoelectronic devices. In this context, the nanostructures of the black Pachliopta aristolochia butterfly which are responsible for its broadband and omnidirectionnal anti-reflecting...

The famous non-iridescent blue of the Morpho butterfly is caused by a 'Christmas tree' like nanostructure which is a challenge for common fabrication techniques. Here, we introduce a method to fabricate this complex morphology utilizing dual beam interference lithography. We add a reflective coating below the photoresist to create a second interfer...

Morpho butterflies are well-known for their iridescence originating from nanostructures in the scales of their wings. These optical active structures integrate three design principles leading to the wide angle reflection: alternating lamellae layers, "Christmas tree" like shape, and offsets between neighboring ridges. We study their individual effe...

This paper presents an analysis technique of the impact of temperature on electrical load. A linear regression based analysis of temperature sensitivity of Bangladesh electrical load is performed for this purpose. The analysis recognizes that the load pattern of Bangladesh Power System (BPS) is heavily dependent on temperature. This study also show...

This paper presents a forecasting technique of the temperature sensitivity of electrical load. Temperature sensitivity of electrical load means the amount of change in load consumption for one degree change in temperature. A linear regression based analysis of temperature sensitivity of Bangladesh power system (BPS) load is performed at first and u...

Solar Home System based rural electrification has seen dramatic progress since the start of the Rural Electrification and Renewable Energy Development Project (RREDP), which is financed by Infrastructure Development Company Limited (IDCOL) since 2003. Recently a technical audit was done for the Solar Home Systems. This paper illustrates the finding...

A quantum mechanical (QM) self-consistent model is developed for nano-MOS devices for high-κ insulator including wave function penetration effect into the gate dielectrics. The effects of different types of interface trap distributions are incorporated. It has been observed that capacitance-voltage (C-V) characteristics are sensitive to the interfa...