Ultrafast active water pump driven by terahertz electric fields

A highly efficient, easy-to-implement, long-ranged and nondestructive way to realize active pumping has been still a great challenge. Here, using molecular dynamics simulations, terahertz electric field (TEF) is employed to stimulate an active pump for water transportation by bias applied in a (6, 6) single-walled carbon nanotube under no external pressure gradient. An ultrafast conductivity (up to approximate to 9.5 ns(-1)) through the pump around a characteristic frequency of 14 THz is found. The excellent pumping ability is attributed to the resonance coupling between the TEF and water molecules, in which water molecules can gain considerable energy continuously to break the binding of hydrogen bonds and the spatial symmetry. This proposed TEF-driven pump design will offer a guide in polar molecule transport through artificial or biological nanochannels, particularly in a controllable, noncontact and large-scale process.