Nanogold and its surprising new properties

Event Date:
2019-11-07T16:00:00
2019-11-07T17:00:00
Event Location:
Hennings 201
Speaker:
Alexandre Brolo (UVic)
Related Upcoming Events:
Intended Audience:
Undergraduate
Local Contact:

Douglas Scott

Event Information:

A variety of new properties emerges in nanostructured metallic materials. These new properties are consequence of the collective excitation of conducting electrons, known as surface-plasmon resonances (SPR). For instance, the color of noble metals, such as gold and silver, can be controlled at the nanoscale by tuning the geometric characteristics of the nanostructures. Surface plasmon (SP) waves can propagate at the surface of thin metal films and this property can be explored for 2D imaging applications. Another very interesting consequence of SPR is the phenomenon of electric field localization. Once the SPR condition is established, metallic nanostructures can act as tiny antennas that capture visible radiation and concentrate it in sub-wavelength regions. Molecules exposed to the localized fields can experience a large increase in their spectroscopic response. This leads to unique spectroscopic phenomena, such as the surface-enhanced Raman scattering (SERS) effect. The optical fields achieved in certain metallic nanostructures can be very strong and only accessible to a very small number of molecules (since they are also confined to very small regions). Ultimately, in certain conditions, SERS allows the detection of single adsorbed species. In this work, we will discuss our efforts in imaging propagating waves on metal films. We will also explore the use of localized SPs  from individual metallic nanoparticles for single molecule localization and spectroscopy.​​

Add to Calendar 2019-11-07T16:00:00 2019-11-07T17:00:00 Nanogold and its surprising new properties Event Information: A variety of new properties emerges in nanostructured metallic materials. These new properties are consequence of the collective excitation of conducting electrons, known as surface-plasmon resonances (SPR). For instance, the color of noble metals, such as gold and silver, can be controlled at the nanoscale by tuning the geometric characteristics of the nanostructures. Surface plasmon (SP) waves can propagate at the surface of thin metal films and this property can be explored for 2D imaging applications. Another very interesting consequence of SPR is the phenomenon of electric field localization. Once the SPR condition is established, metallic nanostructures can act as tiny antennas that capture visible radiation and concentrate it in sub-wavelength regions. Molecules exposed to the localized fields can experience a large increase in their spectroscopic response. This leads to unique spectroscopic phenomena, such as the surface-enhanced Raman scattering (SERS) effect. The optical fields achieved in certain metallic nanostructures can be very strong and only accessible to a very small number of molecules (since they are also confined to very small regions). Ultimately, in certain conditions, SERS allows the detection of single adsorbed species. In this work, we will discuss our efforts in imaging propagating waves on metal films. We will also explore the use of localized SPs  from individual metallic nanoparticles for single molecule localization and spectroscopy.​​ Event Location: Hennings 201