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Path Integrals |
I have been interested in path integrals for a long time used them for the description of a variety of problems in chemical physics. This includes evaluation of path integrals and their applications to tunneling problems (STM), reaction dynamics, and chemical physics of polymers.
- We have studied the tunneling of a particle in presence of coupling to other degrees of freedom: The cases that we have studied are: Tunneling of an electron across the barrier in STM experiments. The potential of the tunneling electron is modified by the image interaction. The image interaction is due to the interaction of the charge of the electron with the surface plasmons. As the tunneling time is expected to be comparable to the 1/frequency of the surface plasmons, one expects dynamical image interaction to be important. We found that dynamical image interaction can modify the barrier significantly. Another problem that we have investigated is the case of tunneling in electrochemical STM experiments.
- A path integral approach to fractional Brownian motion has been developed and investigated. The action for the path integral is similar to the usual one and involves fractional derivatives instead of the usual. Some path integrals have been exactly evaluated.
- Adsorption of polymers on random surfaces.
- N. Chakravarti and K. L. Sebastian: Fractional Brownian Motion Model for polymers. Chemical Physics Letters, 267, 9 (1997).
- K. L. Sebastian: Path Integrals for fractional Brownian motion. Journal of Physics A, 28, 4305 (1995).
- K. Sumithra and K. L. Sebastian: Polymers at chemically random surfaces. Journal of Physical Chemistry, 98, 9312 (1995).
- K. L. Sebastian and K. Sumithra: Adsorption of a polymer on a random surface. Physical Review E, 47, R32, (1993).