Physics of ultrahigh speed electronic devices

Feature sizes of advanced commercial electronic devices are now smaller than the mean free path of the electron collisions with impurities and lattice vibrations. This completely changes the physics of the electron transport. The effective field effect mobility becomes proportional to the device length because the electrons lose their drift momentum in the contacts. The high frequency impedance is strongly affected by the electron inertia and by the phase delays of the opposing electron fluxes in the device channel. The waves of the electron density (plasma waves) enable the device response well into the terahertz (THz) range of frequencies. At high excitation levels, these waves are transformed into the shock waves. The rectification and instabilities of the plasma waves enable a new generation of THz plasmonic devices.