A Review and Application of the Finite-Difference Time-Domain Algorithm Applied to the Schrodinger Equation
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A Review and Application of the Finite-Difference Time-Domain Algorithm Applied to the Schrodinger EquationAbstract
This paper contains a review of the FDTD algorithm as applied to the time-dependent Schrodinger equation, and the basic update equations are derived in their standard form. A simple absorbing boundary condition is formulated and shown to be effective with narrowband wave functions. The stability criterion is derived from a simple, novel perspective and found to give better efficiency than earlier attempts. Finally, the idea of probability current is introduced for the first time and shown how it can be used to radiate new probability into a simulation domain. This removes the need to define an initial-valued wave function, and the concept is demonstrated by measuring the transmission coefficient through a potential barrier.
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References
A. Goldberg, H. M. Schey, and J. L. Schwartz,
“Computer-generated motion pictures of one-
dimensional quantum mechanical transmission
and reflection phenomena,” American Journal of
Physics, vol. 35, no. 3, pp. 177–186, March 1967.
T. Shibata, “Absorbing boundary conditions for the
finite-difference time-domain calculation of the one-
dimensional Schr ̈odinger equation,” Physical Review
B, vol. 42, no. 8, pp. 6760–6763, March 1991.
J. P. Kuska, “Absorbing boundary conditions for the
Schr ̈odinger equation on finite intervals,” Physical
Review B, vol. 46, no. 8, pp. 5000 – 5003, August
D. M. Sullivan, Electromagnetic Simulation Using
the FDTD Method. New York, NY: IEEE Press,
A. Soriano, E. A. Navarro, J. A. Porti, and V. Such,
“Analysis of the finite difference time domain tech-
nique to solve the Schr ̈odinger equation for quantum
devices,” Journal of Applied Physics, vol. 95, no. 12,
pp. 8011 – 8018, June 2004.
D. M. Sullivan and D. S. Citrin, “Determination
of the eigenfunctions of arbitrary nanostructures
using time-domain simulation,” Journal of Applied
Physics, vol. 91, no. 5, pp. 3219–3226, March 2002.
——, “Time-domain simulation of a universal quan-
tum gate,” Journal of Applied Physics, vol. 96, no. 3,
pp. 1540–1546, August 2004.
E. Merzbacher, Quantum Mechanics, 3rd ed. New
York, NY: John Wiley & Sons, 1998.
P. A. Tipler and R. A. Llewellyn, Modern Physics,
rd ed. New York, NY: W. H. Freeman and
Company, 1999.
W. Dai, G. Li, R. Nassar, and S. Su, “On the stability
of the FDTD method for solving a time-dependent
Schr ̈odinger equation,” Numerical Methods in Par-
tial Differential Equations, vol. 21, no. 6, pp. 1140–
, April 2005.
A. Arnold, M. Ehrhardt, and I. Sofronov, “Discrete
transparent boundary conditions for the Schr ̈odinger
equation: Fast calculation, approximation, and sta-
bility,” Communications in Mathematical Science,
vol. 1, no. 3, pp. 501–556, 2003.
Z. Xu and H. Han, “Absorbing boundary conditions
for nonlinear Schr ̈odinger equations,” Physical Re-
view E, vol. 74, no. 3, pp. 037 704–(1–4), March
G. Mur, “Absorbing boundary conditions for the
finite-difference approximation of the time-domain
electromagnetic-field equations,” IEEE Transactions
on Electromagnetic Compatibility, vol. 23, no. 4, pp.
–382, November 1981.
C. Farrell and U. Leonhardt, “The perfectly matched
layer in numerical simulations of nonlinear and
matter waves,” Journal of Optics B: Quantum and
Semiclassical Optics, vol. 7, no. 1, pp. 1–4, January