July 29/30DARPA-meeting1 Technological Basis Fundamental Physics Device Applications Ion Channels, Carbon Nanotubes, wet/dry

July 29/30DARPA-meeting2 Technological Basis Fundamental Physics Device Applications Technological Basis wet/dry/interface Bio-Channels Nanotubes The technological basis is provided by nature The increased knowledge in the chemistry and physics of Ion Channels (location of fixed charges etc.) permits progress in simulation and to learn from nature

July 29/30DARPA-meeting3 Technological Basis Fundamental Physics Device Applications Technological Basis Nanotubes Synthetic techniques are in infancy Laser-ablation (expensive) Arc-evaporation (MWNT) CVD in chamber will give soot to be purified CVD on chip will give NTs in desired locations - Need for control of structure of a single tube Bio-Channels The technological basis is provided by nature The increased knowledge in the chemistry and physics of Ion Channels (location of fixed charges etc.) permits progress in simulation and to learn from nature Nanotubes grow from CoSi islands

July 29/30DARPA-meeting4 Technological Basis Fundamental Physics Device Applications Technological Basis As a self-organized structure, tubes have various symmetry and controllable electronic properties Bio-Channels The technological basis is provided by nature The increased knowledge in the chemistry and physics of Ion Channels (location of fixed charges etc.) permits progress in simulation and to learn from nature Nanotubes Synthetic techniques are in infancy

July 29/30DARPA-meeting5 Technological Basis Fundamental Physics Device Applications Technological Basis Characterization e.g. by Tunneling Spectroscopy Bio-Channels The technological basis is provided by nature The increased knowledge in the chemistry and physics of Ion Channels (location of fixed charges etc.) permits progress in simulation and to learn from nature As a self-organized structure, tubes have various symmetry and controllable electronic properties Nanotubes Synthetic techniques are in infancy

July 29/30DARPA-meeting6 Technological Basis Fundamental Physics

July 29/30DARPA-meeting7 Technological Basis Fundamental Physics Device Applications Fundamental Physics Bio-Channels Nanotubes Classical vs. Quantum Mechanical Description Casimir Forces at nanoscale quantum electrodynamical description - full microscopics vs. continuum theory p1p1p1p1 p2p2p2p2 E J.D.van der Waals, F. London, 1930 H.B.G. Casimir, 1949

July 29/30DARPA-meeting8 Technological Basis Fundamental Physics Device Applications Fundamental Physics Nanotubes p1p1p1p1 p2p2p2p2 E Bio-Channels Classical vs. Quantum Mechanical Description Casimir Forces at nanoscale quantum electrodynamical description - full microscopics vs. continuum theory J.D.van der Waals, F. London, 1930 H.B.G. Casimir, 1949

July 29/30DARPA-meeting9 Technological Basis Fundamental Physics Device Applications Fundamental Physics Bio-Channels Nanotubes Classical vs. Quantum Mechanical Description Multiple scales in modeling Equations of Continuity

July 29/30DARPA-meeting10 Technological Basis Fundamental Physics Device Applications Fundamental Physics Bio-Channels Nanotubes Classical vs. Quantum Mechanical Description Multiple scales in modeling Equations of Continuity Monte-Carlo solution of the Boltzmann transport equation Finite size of the ions !! Quantum Effects : van der Waals, Casimir, DFT

July 29/30DARPA-meeting11 Technological Basis Fundamental Physics Device Applications Fundamental Physics Nanotubes Classical vs. Quantum Mechanical Description Bio-Channels Multiple scales in modeling Equations of Continuity Monte-Carlo solution of the Boltzmann transport equation Finite size of the ions !! Quantum Effects : van der Waals, Casimir, DFT

July 29/30DARPA-meeting12 Technological Basis Fundamental Physics Device Applications Fundamental Physics Nanotubes Multiple scales in modeling Classical vs. Quantum Mechanical Description Continuum theory of elastic deformations with Molecular Dynamics for parametrization Classical electrostatics with atomistic quantum capaciatnce van der Waals Nanotube Electromechanical Switch z,nm , e/nm  Charge Density Profile

July 29/30DARPA-meeting13 Technological Basis Fundamental Physics Device Applications

July 29/30DARPA-meeting14 Technological Basis Fundamental Physics Device Applications Bio-Channels Nanotube FETs High I ON /I OFF ratio (approaching infinity) Operation voltage: low Device characteristics: slow

July 29/30DARPA-meeting15 Technological Basis Fundamental Physics Device Applications Nanotube FETs Significant improvement (10 5 ) of I ON /I OFF ratio was claimed in 4 years Best NT-FETs operate as unconventional SB-FET S.J. Tans, Ph. Avouris, C. Dekker, Ph. Avouris, Bio-Channels High I ON /I OFF ratio (approaching infinity) Operation voltage : low Device characteristics : slow

July 29/30DARPA-meeting16 Technological Basis Fundamental Physics Device Applications Nanotube FETs Significant improvement (10 5 ) of I ON /I OFF ratio was claimed in 4 years Best NT-FETs operate as unconventional SB-FET S.J. Tans, Ph. Avouris, C. Dekker, Ph. Avouris, 2002.

July 29/30DARPA-meeting17 Technological Basis Fundamental Physics Device Applications Nanotube FETs Significant improvement (10 5 ) of I ON /I OFF ratio was done in 4 years Best NT-FETs operate as unconventional SB-FET Sub-threshold slope ?? S.J. Tans, Ph. Avouris, C. Dekker, Ph. Avouris, High sensitivity to oxygen Nanotube artificial ion-atom- molecule channels

July 29/30DARPA-meeting18 Technological Basis Fundamental Physics Device Applications Conclusions Powerful multi scale simulation approaches to both Biological Ion Channels and Carbon Nanotubes possible in near future Both areas can learn from each other; the wet-dry interface being of particular interest Interesting device opportunities: low power off/on -> 0 molecular transport in dry world