Opportunity at Naval Research Laboratory (NRL)
Directional Self-Assembly of Three-Dimensional Structures on Nano and Submicrometer Scale
Naval Research Laboratory, Center for Bio/Molecular Science & Engineering
||Washington, DC 203755321
|Ratna, Banahalli R.
The overall goal of this program is to develop new approaches to control the three-dimensional self-assembly of inorganic particles using soft organic bridges and templates. For example, we have demonstrated the use of three-dimensionally ordered bicontinuous cubic phase exhibited by surfactants and lipids as a matrix to synthesize monodispersed metal and semiconductor nanoparticles. We have shown that this method can be extended to develop nanocrystalline phosphors with very good photo- and cathodoluminescence. These nanophosphors are currently being tested for its electroluminescence properties and as optical probes for biodetection. Another area of interest in this program is the development of photonic band gap (PBG) materials for the optical and infrared region. A three-dimensional periodic modulation of the refractive index in a material can result in a band structure for photons similar to the band structure for electrons in a semiconductor. PBG materials would prevent spontaneous emission of light with frequencies in the gap, a potentially very valuable tool for making more efficient, threshold-free lasers. Furthermore, defects within a PBG material would allow gap frequencies to propagate only in the region of the defect, resulting in microscopic waveguides or resonant cavities. Thermodynamically driven colloidal self-assembly of particles can lead to only a few structures such as fcc or hcp. Under this program, we propose to develop bio-inspired organic bridges to develop clusters of particles which can be used to create three-dimensional structures that are not possible to achieve by traditional colloidal self-assembly.
Colloidal crystal; Core-shell particles; DNA; Luminescence; Molecular bridge; Nanoparticles; Photonic; Photonic band gap; Self-assembly;
Open to U.S. citizens and permanent residents
Open to Postdoctoral applicants