Single Nanoparticle Detection using on-chip Notched Ring Resonator
- PDF / 553,727 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 52 Downloads / 259 Views
Single Nanoparticle Detection using on-chip Notched Ring Resonator S. Wang1 and Y. Yi2, 3, 1 * 1
Massauchusetts Institute of Technology, Cambridge, MA 02139 New York University, New York, NY 10012 3 CUNY Graduate Center, New York, NY 10016 2
ABSTRACT A new photonic structure was demonstrated to achieve strong optical coupling between nanoparticle and photonic molecule by utilizing a notched micro ring resonators. By creating a notch in the ring resonator and putting a nanoparticle inside the notch, large spectral shifts and splittings at nm scale can be achieved, compared to only pm scale observed by fiber tip evanescently coupled to the surface of microsphere, thereby significantly lowered the quality factor requirement for single nanoparticle detection. The ability for sorting the type of nanoparticles due to very different mode shift and splitting behavior of dielectric and metallic nanoparticles is also emphasized. *e-mail: [email protected]
Nano scale photonic devices are very promising to achieve manipulation of photons at chip scale and having broad applications in renewable energy (photovoltaic cells, solid state lighting), telecommunications and bio medical field1. Recently, it was found that the electromagnetic modes of certain photonic devices are very similar to the electronic wave function of molecules2-3. One of the most interesting examples is micro ring resonators, especially when we arrange two or more microresonators together within optical coupling regime, the electromagnetic modes of the whole structure are very similar to the bonding (symmetric) or anti bonding (antisymmetric) electronic wave function modes formed in molecules4-7. It is interesting to study the photonic molecule of various structures using optical techniques and it may further improve our understanding of the real molecular structures. Nanoparticle has played a key role in nanophotonics and has found many applications in medicine, drug delivery, solar cells and sensors. It is also an important tool for the study of many nano scale structures and is used to interact with nano scale devices, as critical information could be obtained to understand their characteristics. Recently, nanoparticles have been heavily used in the optical sensor area, as fast, non-invasive, and potentially label-free techniques are becoming more important for biosensing, gas sensing, chemical sensing. Single nanoparticle detection is one of the ultimate goals for a sensing device and represents sensing at the extreme. In recent years, many novel methods have been utilized to realize nanoparticle detection. For example, metal nanoparticles are used as contrast agents in bio molecule sensing, semiconductor nanoparticles are used as single photon emitters in quantum information processing, and as fluorescent markers for biological processes, nanoshells with special engineering methods are used for cancer therapies and photothermal tumor ablation, polymer nanoparticles are employed as calibration standards and probes in biological imaging in functionalized f
Data Loading...
