Does the classically chaotic Henon–Heiles oscillator exhibit quantum chaos under intense laser fields?

Pramana

Neetu Gupta¹  B M Deb2² 

[1] Theoretical Chemistry Group, Department of Chemistry, Panjab University, Chandigarh 160 014, India$$;S.N. Bose National Centre for Basic Sciences, JD Block, Sector-III, Salt Lake, Kolkata 700 098, India and Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, India$$

关键词: Quantum chaos;    coupled oscillators;    multiphoton processes;    high-order harmonics generation.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The quantum dynamics of an electron moving under the Henon–Heiles (HH) potential in the presence of external time-dependent (TD) laser fields of varying intensities have been studied by evolving in real time the unperturbed ground-state wave function 𝜙(𝑥, 𝑦, 𝑡) of the HH oscillator. The TD Schröinger equation is solved numerically and the system is allowed to generate its own wave packet. Two kinds of sensitivities, namely, sensitivity to the initial quantum state and to the Hamiltonian, are examined. The threshold intensity of the laser field for an electron moving in the HH potential to reach its continuum is identified and in this region quantum chaos has been diagnosed through a combination of various dynamical signatures such as the autocorrelation function, quantum `phase-space' volume, `phase-space' trajectory, distance function and overlap integral (akin to quantum fidelity or Loschmidt echo), in terms of the sensitivity towards an initial state characterized by a mixture of quantum states (wave packet) brought about by small changes in the Hamiltonian, rather than a `pure' quantum state (a single eigenstate). The similarity between the HH potential and atoms/molecules in intense laser fields is also analyzed.

【 授权许可】

Unknown