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Presented by: Kyle Hershey Jason Maldonis. “Five-dimensional optical recording mediated by surface plasmons in gold nanorods ” - Zijlstra , Chon, Gu. Five Dimensions: 3x Spatial Dimensions Polarization Wavelength. What does 5D mean?.
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Presented by: Kyle Hershey Jason Maldonis “Five-dimensional optical recording mediated by surface plasmonsin gold nanorods” -Zijlstra, Chon, Gu
Five Dimensions: • 3x Spatial Dimensions • Polarization • Wavelength What does 5D mean?
Quantized electron oscillation at surface between dialectric and metal. Can be excited by photons. Wavelength needed for excitation dependent on aspect ratio. Can only be excited by photons at certain incident angles. surface plasmons Schematic representation of an electron density wave propagating along a metal – dielectric interface. The charge density oscillations and associated electromagnetic fields are called surface plasmon-polaritonwaves. The exponential dependence of the electromagnetic field intensity on the distance away from the interface is shown on the right. These waves can be excited very efficiently with light in the visible range of the electromagnetic spectrum.
Two photons used to excite molecules Then emit a single photon two photon luminescence (TPL) http://www.ncl.ac.uk/bioimaging/techniques/2photon/
One of the photons can excite SPR, increasing the electric field around particle Creates higher chance of emitting a photon Since SPR depends on incident angle, we have polarization dependence in TPL TPL With nanorods http://ej.iop.org/images/0957-4484/24/7/075201/Full/nano447839f2_online.jpg
Fempto second laser pulse One of two polarizations One of three wavelengths If polarization and wavelength matches nanorod’s orientation and aspect ratio then it melts Melts only if laser is focused on that pixel (in 3D space) Writing data by melting nanorods
“Pixels” are ~ 500nm x 500nm Notice selective reshaping Experimental results (Writing) Before 100 nm After 100 nm
TPL has much higher angular dependence allowing for two distinct polarizations Other polarizations and wavelengths are unaffected (d-f) Reading in data
Disclaimer: single write only Information density results
Five-dimensional optical recording mediated by surface plasmons in gold nanorods Peter Zijlstra, James W. M. Chon, Min Gu • Surface plasmon effects on two photon luminescence of gold nanorods Da-Shin Wang, Fu-Yin Hsu, Chii-WannLin • en.wikipedia.org/wiki/Memory_storage_density • www.pctechguide.com/hard-disks/hard-disk-hard-drive-construction • www.techradar.com/us/news/computing-components/storage/how-the-humble-hard-drive-is-made-667183 references