Research

Goals and Motivation

The research in the Laboratory for Biologically Inspired Photonic Engineering is focused on the fundamental and applied aspects of conceiving and fabricating multifunctional, hierarchically-structured, bio-inspired material systems with particular focus on stimuli-responsive and dynamically tunable optical performance.

In this regard, we can benefit in several ways from highly sophisticated material solutions that have convergently evolved in various organisms. In particular, we explore design concepts found in biological photonic architectures, seek to understand the mechanisms underlying morphogenesis of biological optical materials, aim to devise viable manufacturing strategies that can benefit from insight in biological formation processes and the use of established synthetic routines alike, and ultimately strive to realize new photonic materials with tailor-made optical properties.

Projects

Our project portfolio broadly covers research in biological and bio-inspired multifunctional materials with an optical function or application potential in novel optical technology. A summary is shown in the graphic below and some project details are provided beneath:

1. Color-tunable, stimuli-responsive photonic fibers

   Project lead: Joseph Sandt (graduate student)
   Contributors: Christian Argenti, Marcus Urann (undergraduate students)
   

   This project is focused on the design, and manufacture of tunable photonic fibers. Potential applications include pressure indicators in bandages, color-dynamic textiles, infrastructural health monitoring, and applications in medical and civil engineering, where the detection of large stresses, strains, or deformations is crucial.

   Color-tunable photonic fiber. a) Scanning electron micrograph of a fiber’s morphology. b) Color variation due to fiber deformation. c) Tuning of reflection peak wavelength as a function of axial strain. d) Concept for scalable fiber manufacture.

   Related publications:

   • J. Sandt et al. (in preparation).
   • M. Kolle et al. Adv. Mater. 25, 2239-2245 (2013).   
    
    

2. Reconfigurable, emulsion-based micro lenses

   Project lead: Sara Nagelberg (graduate student)
   Contributors: Lauren Zarzar (PostDoc, MIT Dept. of Chemistry), Natalie Nicolas (undergraduate student)
   

   Tunable micro-optical elements are formed from complex emulsions. The resulting micro lenses can be controllably reconfigured using a variety of stimuli. Potential applications include stereoscopic imaging devices in microfluidics, integral imaging displays, autonomous light coupling enhancers for photovoltaics and self-adjusting fiber-couplers.

   Reconfigurable micro-lenses. a) Controlled variation in lens morphology. Lens diameter ~100µm. b) Finite difference time domain modeling of light propagating through a reconfigurable micro-lens. The internal morphology governs the lenses’ focal length.

   Related publications:

   • S. N. Nagelberg et al. (in preparation).
   • L. Zarzar et al. Nature 518, 520-524 (2015).   
    
    

3. Pixelated, photonic surfaces

   Project leads: Cécile Chazot, Chris Wing (graduate students)
   Contributors: Maik Scherer, Alvin Tan

   Hierarchical, length scale bridging arrangements of different optical features by using suitable combinations of self-assembly, template-replication and micro-fabrication, enables us to create surfaces with tens of thousands of identical optical components in one square centimeter. The visual appearance of theses surfaces changes strongly depending on the local surface orientation, which makes them suitable for localization of deformations with high spatial resolution. The incorporation of active elements such as laser dyes, and quantum dots enables us to create micro-scale emitters.

   Pixelated photonic surfaces. a) Schematic of a single pixel resonance cavity. Cavity diameter ~ 5µm. b) Finite difference time domain modeling of light resonating in a cavity. c)Fluorescence of laser dye incorporated in concave reflectors.

   Related publications:

   • S. Cormier et al., (in preparation).
   • G. England et al. Proc. Natl. Acad. Sci. 111, 15630-15634 (2014).   
   • M. Kolle et al., Nature Nanotech. 5, 511-515 (2010).   
    
    

4. Morphogenesis and engineering of biological photonic materials

   Project lead: Anthony McDougal (graduate student)
   Contributors: Zahid Yaqoob (Research Scientist, MIT Laser Biomedical Research Center), William Liberti (Boston University)

   Many organisms have mastered the controlled growth of hierarchical, multifunctional nano- and microstructures that show strong, optimized interactions with light. To do this, living systems employ unique physical phenomena and control mechanisms to precisely produce these functional material morphologies. We are studying the wings of the Painted Lady butterfly during metamorphosis with the aim of tracking scale development with high temporal and spatial resolution during chrysalis metamorphosis, in order to elucidate the underlying physical phenomena and control mechanisms. Our goal is to reveal key factors that we can adjust to modify structure formation in the organisms in-vivo, or in isolated cultures of scale-forming cells in-vitro.

   Biological optical structures.. a) The “Painted Lady” butterfly, Vanessa cardui. b, c) Scales on the butterfly’s wings at different magnifications. d) Development of the chrysalis.

   Related publications:

   • A. Dinwiddie et al., Dev. Biol. 392, 404-418 (2014).  
   • Y. Ohno et al., PLoS One 10, e0128332 (2015).  
    
    

5. Biomineralization of functional marine materials

   Project lead: Ling Li (PostDoc, Harvard), Mathias Kolle
   Contributors: Natalie Nicolas (undergraduate student)

   This proposed effort is aimed at revealing the mechanisms that enable the blue-rayed limpet Patella pellucida to form a translucent protective shell with an integrated photonic structure. We will use time-resolved micro-scale imaging and sensing approaches to study the formation mechanisms employed by the limpet to control the growth of its hierarchical functional shell morphology and quantify the impact that environmental parameters have on the underlying biomineralization processes. This will provide insight into low-temperature strategies for synthesizing biological and bio-inspired multifunctional materials and allow for the quantification of the influence of anthropogenic ocean acidification on the abilities of marine organisms to form shells.

   A biomineralized multifunctional material.. a) The blue-rayed limpet Patella pellucida. b, A single blue stripe in the limpets translucent shell. c) Scanning electron micrograph (SEM) of a shell cross-section located within the blue stripe area. d) A live limpet prepared for in-vivo imaging experiments. The inset shows the limpet with a small magnetic backpack. e) The limpet seen from below. f) At its growth edge all structures of interest surface as seen in this combined optical microscopy and SEM image. In-vivo experiments can reveal insights into shell formation processes.

   Related publications:

   • L. Li et. Nature Commun. 6, 6322 (2015).