Open Access. Powered by Scholars. Published by Universities.®

Nanoscience and Nanotechnology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Other Nanotechnology Publications

Discipline
Keyword
Publication Year

Articles 31 - 35 of 35

Full-Text Articles in Nanoscience and Nanotechnology

In Vitro And In Vivo Two-Photon Luminescence Imaging Of Single Gold Nanorods, Haifeng Weng, Terry B. Huff, Daniel A. Zweifel, Wei He, Philip S. Low, Alexander Wei, Ji-Xin Cheng Nov 2005

In Vitro And In Vivo Two-Photon Luminescence Imaging Of Single Gold Nanorods, Haifeng Weng, Terry B. Huff, Daniel A. Zweifel, Wei He, Philip S. Low, Alexander Wei, Ji-Xin Cheng

Other Nanotechnology Publications

Gold nanorods excited at 830 nm on a far-field laser-scanning microscope produced strong two-photon luminescence (TPL) intensities, with a cos(4) dependence on the incident polarization. The TPL excitation spectrum can be superimposed onto the longitudinal plasmon band, indicating a plasmon-enhanced two-photon absorption cross section. The TPL signal from a single nanorod is 58 times that of the two-photon fluorescence signal from a single rhodamine molecule. The application of gold nanorods as TPL imaging agents is demonstrated by in vivo imaging of single nanorods flowing in mouse ear blood vessels.


Theoretical Investigation Of Surface Roughness Scattering In Silicon Nanowire Transistors, Jing Wang, Eric Polizzi, Avik Ghosh, Supriyo Datta, Mark Lundstrom Jul 2005

Theoretical Investigation Of Surface Roughness Scattering In Silicon Nanowire Transistors, Jing Wang, Eric Polizzi, Avik Ghosh, Supriyo Datta, Mark Lundstrom

Other Nanotechnology Publications

Using a full three-dimensional (3D), quantum transport simulator, we theoretically investigate the effects of surface roughness scattering (SRS) on the device characteristics of Si nanowire transistors (SNWTs). The microscopic structure of the Si/SiO2 interface roughness is directly treated by using a 3D finite element technique. The results show that (1) SRS reduces the electron density of states in the channel, which increases the SNWT threshold voltage, and (2) the SRS in SNWTs becomes less effective when fewer propagating modes are occupied, which implies that SRS is less important in small-diameter SNWTs with few modes conducting than in planar metal-oxide-semiconductor field-effect-transistors …


Role Of Phonon Scattering In Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom May 2005

Role Of Phonon Scattering In Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom

Other Nanotechnology Publications

The role of phonon scattering in carbon nanotube field-effect transistors 􏰏CNTFETs􏰀 is explored by solving the Boltzmann transport equation using the Monte Carlo method. The results show that elastic scattering in a short-channel CNTFET has a small effect on the source-drain current due to the long elastic mean-free path (mfp)(~ 1µm). If elastic scattering with a short mfp were to exist in a CNTFET, the on current would be severely degraded due to the one-dimensional channel geometry. At high drain bias, optical phonon scattering, which has a much shorter mfp (-10 nm), is expected to dominate, even in a short-channel …


Quantum Mechanical Analysis Of Channel Access Geometry And Series Resistance In Nanoscale Transistors, R. Venugopal, S. Goasguen, S. Datta, M. S. Lundstrom Jan 2004

Quantum Mechanical Analysis Of Channel Access Geometry And Series Resistance In Nanoscale Transistors, R. Venugopal, S. Goasguen, S. Datta, M. S. Lundstrom

Other Nanotechnology Publications

We apply a two-dimensional quantum mechanical simulation scheme to study the effect of channel access geometries on device performance. This simulation scheme solves the nonequilibrium Green’s function equations self-consistently with Poisson’s equation and treats the effect of scattering using a simple approximation inspired by Bu ̈ttiker. It is based on an expansion of the device Hamiltonian in coupled mode space. Simulation results are used to highlight quantum effects and discuss the importance of scattering when examining the transport properties of nanoscale transistors with differing channel access geometries. Additionally, an efficient domain decomposition scheme for evaluating the performance of nanoscale transistors …


Performance Projections For Ballistic Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom, Supriyo Datta Apr 2002

Performance Projections For Ballistic Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom, Supriyo Datta

Other Nanotechnology Publications

The performance limits of carbon nanotube field-effect transistors 􏰎CNTFETs􏰁 are examined theoretically by extending a one-dimensional treatment used for silicon metal – oxide – semiconductor field-effect transistors 􏰎MOSFETs􏰁. Compared to ballistic MOSFETs, ballistic CNTFETs show similar I–V characteristics but the channel conductance is quantized. For low-voltage, digital applications, the CNTFET with a planar gate geometry provides an on-current that is comparable to that expected for a ballistic MOSFET. Significantly better performance, however, could be achieved with high gate capacitance structures. Because the computed performance limits greatly exceed the performance of recently reported CNTFETs, there is considerable opportunity for progress in …