Momentum-dependent field-effect transistor.

The silicon-based field-effect transistor (FET) is approaching the physical limits for the prominent short-channel effects and the sequent leakage currents under the conventional paradigm. Here, we propose a momentum-dependent field-effect transistor (MD-FET) to address this issue, in which a monolayer 2D semiconductor is sandwiched by two cross 1D carbon nanotube electrodes. The MD-FET enables a perfect off state, as the elastic tunneling is forbidden by the momentum mismatch between the cross 1D contacts. It can also access a substantial on state, because the momentum mismatch can be compensated by the electron-phonon scattering in a 2D channel. The MD-FET with sub-1-nm channel thus exhibits high on/off ratios of ~10, which breaks through the theoretical limit on the short-channel effect. The MD-FET opens up a previously unknown paradigm to further scale down transistors beyond silicon and inspires a promising solution for the post-Moore era.