Research I: Micro-/nano- additive manufacturing & Nanoimprinting
1. Functional materials.
2. Novel process development, modulation, and control.
3. Novel applications.
Research II: Functional metamaterials/ metasurfaces
1. Reconfigurable electromagnetic/mechanical metamaterials.
2. Novel applications: advanced sensing and imaging, photon management, energy bandgap, etc.
Previous Research Projects
High Speed Additive Manufacturing of Optical Devices
Advancements in additive manufacturing (3D printing) technology have the potential to transform the manufacture of customized optical elements. However the inherent speed‐accuracy trade‐off seriously constrains the practical applications of 3D‐printing technology in the optical realm.
We developed a new method featuring a significantly faster fabrication speed without compromising the fabrication accuracy required to 3D‐print customized optical components. A high‐speed 3D‐printing process with sub-voxel‐scale precision (sub 5 µm) and deep sub-wavelength (sub 7 nm) surface roughness by employing the projection micro‐stereolithography process and the synergistic effects from grayscale photo-polymerization and the meniscus equilibrium post‐curing methods ha been demonstrated. This work elucidates the unprecedented potential of 3D printing techniques for optical applications, which will further lead to a plethora of novel devices with a tremendous impact on free-form optics and biomedical imaging.
- Xiangfan Chen, et al., “High-speed 3D Printing Millimeter-Size Customized Aspheric Imaging Lens with Sub-7 nm Surface Roughness”, Advanced Materials, 30, 1705683 (2018)
Scalable Nanomanufacturing of Dynamic & Reconfigurable Metasurfaces/Metamaterials
Optical control over elementary molecular vibration establishes foundation of a wide range of optical linear and nonlinear phenomena. However, experimental demonstration of the coherently driven molecular vibration remains a challenge task due to the inherently weak optical force imposed on natural materials. We develop unique metasurfaces comprising reconfigurable “metamolecules” that support spatially overlapping electromagnetic resonance at optical frequency and vibration resonance at GHz. The coherent coupling of those two distinct resonance modes manifests strong optical forces upon the inherent compliance of the metamolecules, which further allows for the experimental demonstration of all-optical modulation of the transmitted light at 1.85 GHz.
This work is not only promising for applications in optical isolation, filtering, and signal processing, it also sets the stage for exploiting the broad range of the non-linear optical phenomena by providing a completely new architecture for facilitating strong optical force interactions.
- Xiangfan Chen*, Biqin Dong, Chen Wang, Fan Zhou, and Cheng Sun*. “Hyperbolic dispersion via distinct antisymmetric orderings of 2D artificial magnetic dipole array”, ACS Photonics, 5, 11, 4469-4475 (2018)
- Biqin Dong*, Xiangfan Chen*, et al., “Gigahertz All-Optical Modulation Using Reconfigurable Nanophotonic Metamolecules”, Nano Letters, 16 (12), 7690-7695 (2016) (* Equal Contribution, Co-First Author)
- Fan Zhou, Chen Wang, Biqin Dong, Xiangfan Chen, Zhen Zhang, Cheng Sun, “Scalable nanofabrication of U-shaped nanowire resonators with tunable optical magnetism”, Optics Express, 24, 6367-6380 (2016)