The tunneling dynamics of one-and two-dimensional cubic oscillators Ε½ . having randomly fluctuating harmonic force constants K are studied numerically by t invoking the time-dependent Fourier grid Hamiltonian method. The influence of the frequency and strength of the fluctuation on the tunneling pro
On the tunneling dynamics of a cubic oscillator with a time-dependent harmonic frequency
β Scribed by Pranab Sarkar; Satrajit Adhikari; S.P. Bhattacharyya
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 397 KB
- Volume
- 252
- Category
- Article
- ISSN
- 0009-2614
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β¦ Synopsis
The dynamics of a 1-d cubic oscillator having a time-dependent harmonic force constant is studied numerically by invoking the time-dependent Fourier grid Hamiltonian method. The temporal variation in K t causes the tunneling rate constant to decrease or increase, depending upon the nature of the time-dependence of K. For the exponentially increasing 0v or decreasing force constant, the intrinsic tunneling rate constant (ktu n) (in the limit of zero rate of relaxation of the harmonic force constant) is obtained by extrapolation of kt~n(l/~-) to 1/~" ~ 0. The kΒ°~ computed this way compares well with those obtained from the complex scaled Fourier grid Hamiltonian method. The effects of changing the form of the time-dependence of K are analysed and the possibility of mapping real systems onto the present model is explored.
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