Nanoscale localization of electromagnetic fields near metallic nanostructures underpins the fundamentals and applications of plasmonics. The unavoidable energy loss from plasmon decay, initially seen as a detriment, has now expanded the scope of plasmonic applications to exploit the generated hot carriers. However, quantitative understanding of the spatial localization of these hot carriers, ak...

While the field of plasmonics has grown significantly in recent years, the relatively high losses and limited material choices have remained a challenge for the development of many device concepts. The decay of plasmons into hot carrier excitations is one of the main loss mechanisms; however, this process offers an opportunity for the direct utilization of loss if excited carriers can be collec...

We report an optical study of charge transport in graphene. Diffusion of hot carriers in epitaxial graphene and reduced graphene-oxide samples are studied using an ultrafast pump-probe technique with a high spatial resolution. Spatiotemporal dynamics of hot carriers after a pointlike excitation are monitored. Carrier-diffusion coefficients of 11 000 and 5500 cm2 s−1 are measured in epitaxial gr...

Long lifetimes of hot carriers can lead to qualitatively new types of responses in materials. The magnitude and time scales for these responses reflect the mechanisms governing energy flows. We examine the microscopics of two processes which are key for energy transport, focusing on the unusual behavior arising due to graphene's unique combination of material properties. One is hot carrier gene...

Hot-carrier-induced degradation of MOSFET parameters over time is an important reliability concept in modern microcircuits. High energy carriers also called hot carriers are generated in the MOSFET by the large channel electric field near the drain region. The electric field accelarates the carriers to effective temperatures well above the lattice temprature. These hot carriers transfer energy ...

We report on the intrinsic optoelectronic response of high-quality dual-gated monolayer and bilayer graphene p-n junction devices. Local laser excitation (of wavelength 850 nanometers) at the p-n interface leads to striking six-fold photovoltage patterns as a function of bottom- and top-gate voltages. These patterns, together with the measured spatial and density dependence of the photoresponse...

This paper discusses the low-frequency (LF) noise in submicron nMOSFETs under controlled transistor aging by hot-carrier stress. Both traditional, steady-state LF noise as well as the LF noise under periodic large-signal excitation were found to increase upon device degradation, for both hydrogen passivated and deuterium passivated Si–SiO2 interfaces. As hot-carrier degradation is slower in deu...

Hot carrier-induced spin dynamics is analyzed in epitaxial Au/Fe/MgO(001) by a time domain approach. We excite a spin current pulse in Fe by 35 fs laser pulses. The transient spin polarization, which is probed at the Au surface by optical second harmonic generation, changes its sign after a few hundred femtoseconds. This is explained by a competition of ballistic and diffusive propagation consi...