[Paper Review] First Evidence of Near-Infrared Partial Photonic Bandgap in Polymeric Rod-Connected Diamond Structure

Lifeng Chen, Mike P. C. Taverne+6 more|arXiv (Cornell University)|Jan 15, 2015

Diamond and Carbon-based Materials ResearchMaterials Science1 citations

TL;DR

This study presents the first experimental evidence of a partial photonic bandgap in a low-index polymeric rod-connected diamond (RCD) photonic crystal structure at near-infrared wavelengths. Fabricated via two-photon polymerization and characterized using angular-resolved Fourier image spectroscopy, the structure exhibits good agreement between simulated and measured transmission and reflection spectra for both P- and S-polarizations, confirming its photonic bandgap behavior in the near-infrared range.

ABSTRACT

We present the simulation, fabrication, and optical characterization of low-index polymeric rod-connected diamond (RCD) structures. Such complex three-dimensional photonic crystal structures are created via direct laser writing by two-photon polymerization. To our knowledge, this is the first measurement at near-infrared wavelengths, showing partial photonic bandgaps for this structure. We characterize structures in transmission and reflection using angular resolved Fourier image spectroscopy to visualize the band structure. Comparison of the numerical simulations of such structures with the experimentally measured data show good agreement for both P- and S-polarizations.

Motivation & Objective

• To demonstrate the existence of a partial photonic bandgap in a low-index polymeric rod-connected diamond (RCD) photonic crystal at near-infrared wavelengths.
• To fabricate complex three-dimensional photonic crystal structures using direct laser writing with two-photon polymerization.
• To experimentally characterize the optical response of the RCD structure through transmission and reflection measurements.
• To validate numerical simulations of the RCD structure against experimental data for both P- and S-polarized light.
• To establish a benchmark for future development of low-index photonic crystals using polymer-based materials.

Proposed method

• Fabrication of three-dimensional polymeric rod-connected diamond (RCD) structures using direct laser writing via two-photon polymerization.
• Simulation of the optical properties of the RCD structure to predict photonic bandgap behavior in the near-infrared range.
• Employment of angular-resolved Fourier image spectroscopy to measure transmission and reflection spectra across varying incident angles.
• Comparison of simulated and experimentally measured optical responses for both P- and S-polarized light to validate structural and optical fidelity.
• Use of numerical modeling to predict band structure and correlate with experimental data for verification.
• Analysis of the optical response across the near-infrared spectrum to identify bandgap features.

Experimental results

Research questions

• RQ1 Does the polymeric rod-connected diamond structure exhibit a partial photonic bandgap in the near-infrared wavelength range?
• RQ2 How accurately do numerical simulations predict the optical response of the fabricated RCD structure for both P- and S-polarizations?
• RQ3 To what extent do experimental transmission and reflection measurements align with simulated band structure predictions?
• RQ4 Can angular-resolved Fourier image spectroscopy effectively visualize the photonic band structure of complex 3D polymeric photonic crystals?
• RQ5 What is the role of low refractive index contrast in enabling observable photonic bandgap effects in polymer-based RCD structures?

Key findings

• This study presents the first experimental measurement of a partial photonic bandgap in a polymeric rod-connected diamond structure at near-infrared wavelengths.
• The fabricated RCD structure exhibits a measurable photonic bandgap effect, confirmed by angular-resolved transmission and reflection spectroscopy.
• Good agreement is observed between simulated and measured optical responses for both P- and S-polarized light, validating the simulation model.
• The use of low-index polymers in a three-dimensional RCD architecture enables detectable photonic bandgap behavior in the near-infrared range.
• Angular-resolved Fourier image spectroscopy successfully visualized the band structure of the complex 3D photonic crystal.
• The results demonstrate the feasibility of using two-photon polymerization to create functional photonic crystals with tunable optical properties in low-index materials.