Stochastic resonance in nanoscale systems

• Author / Creator

  Saha, Aditya

• This thesis considers the possibility of stochastic resonance (SR) in the following nanoscale systems:
  (i) hard-threshold devices; (ii) averaging structures of carbon nanotubes (CNTs); (iii) myoglobin atoms; and finally (iv) tubulin dimers. The description of SR is carried out using Kramers' rate theory in the adiabatic two-state approximation for continuous systems and using Shannon's information theoretic formalism for systems with static nonlinearities. The effective potentials are modelled by asymmetric or symmetric bistable wells in a single reaction co-ordinate. Quantum considerations have not been invoked. Hence, all results are implicitly valid in the high-temperature regime of relevance to industrial applications.
  It is established that information transmitted by arrays of identical CNTs is maximized by non-zero noise intensities and that the response of myoglobin and tubulin dimers to ambient molecular forces (as described by the signal-to-noise ratio or SNR) is enhanced by increasing temperature. Sample calculations are shown for solvent fluctuations, ligand interactions and dipole oscillations. These results can be used to explain: (i) the effects of temperature observed in fabrication processes for CNTs;
  (ii) the dynamical transition observed in myoglobin and (iii) the 8.085 MHz resonance observed in microtubules.

• Subjects / Keywords

  • Stochastic resonance

• Graduation date

  Spring 2011

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3V646

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.