Ultrafast Intense Molecular Photonics-from Femto to Attosecond Laser Chemistry

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We explore new nonperturbative models and simulations which are based on 3 fundamental PDE,s(Partial Diff Eqns):TDSE(Time-Dependent Schroedinger Equation),its relativistic version TDDE(Time-Dependent Dirac Equation) and laser Maxwell equations.The numerical solutions cover nuclear femtoseconds(1fs=10**-15s) to,electron attoseconds(1 asec=10**-18s) .Compute Canada,s large memory computers allow to perform “numerical experiments” on new problems,nonperturbative issues in the applications of ultrafast intense lasers to ultrafast imaging ,visualization and control of matter on the above time scales. Our research will develop modelling and simulations of the nonlinear responses of molecules to new asec “circularly” polarized pulses as proposed in our 1995 paper cited below in [1].Currently intense laser research in Photonics is limited to linear polarization.We have proposed in 1995 using bichromatic co and counter -rotating circular pulses to generate circular HHG(High Order Harmonic Generation) and “circularly” polarized asec pulses , new tools for generating coherent superpositions of quantum electron “circular currents” as opposed to stationary quantum states in Coherent Control and Quantum Information.The interaction of molecules with intense circularly polarized pulses is a new “chapter” in science Our original proposal to enhance circular HHG as new sources of circular “asec “pulses will be investigated in more detail theoretically,and numerically[1] to explore and include Coriolis interactions, intense magnetic fields generated inside molecules from circular laser induced currents ,relativistic effects such as enhancement of spin-orbit interactions. In particular 3 new research directions will be focused on:(1)-Chirality- opposite laser field helicities produce different direction currents which are very small due to weak laser magnetic fields. Measuring chiral molecular geometries requires higher field intensities which will generate strong currents and their own magnetic fields and has never been considered in chirality models and will be investigated in detail. (2)- Circular XRays-Circular HHG from bichromatic circular pulses will be investigated as a function of pulse frequencies ,shapes and intensities to optimize circularly polarize XRay.generation.Such XRays will serve to ionize core-electrons for new ultrafast chemical reactions.The addition of intense IR pulses will be investigated to promote charge migration between neighboring ionized cores ,a new effect never explored before (3)-exchange of photon-electron-nuclear momenta,is a new nonadiabatic molecular phenomenon.strongest with circular pulses[2].We are developping ;in Compute Canada,s programs a new relativistic molecular TDDE code using our own Split-Operator methods to include in the new science-Attochemistry electron spin,multiphoton momentum exchange,[1]ADBandrauk,JGuo,KJYuan,,JOpt,19,124016(2017);[2]S.Chelkowski,AD.Bandrauk,PBCorkum,Phys Rev Lett 113,263005(2015).**