2011/02/16 by J Villavicencio, I Maldonado, E Cota +2
Physics and Astronomy · #Electron #Floquet theory #Fourier series #Fourier transform #Hamiltonian (control theory) #Mechanical and Optical Resonators #Parity (physics) #Quantum and electron transport phenomena #Quantum chaos and dynamical systems #Quantum dot #Quantum tunnelling #cond-mat.mes-hall
paper · pdf · doi:10.1088/1367-2630/13/2/023032
published as New Journal of Physics 13 (2011) 023032
openalex publication_date 2011/02/16 · arxiv created 2011/03/08 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The dynamics of electrons in ac-driven double quantum dots have been extensively analyzed by means of Floquet theory. In these systems, coherent destruction of tunneling has been shown to occur for certain ac field parameters. In this work we analyze, by means of Floquet theory, the electron dynamics of a triple quantum dot in series attached to electric contacts, where the central dot position oscillates. In particular, we analyze the quasienergy spectrum of this ac-driven nanoelectromechanical system as a function of the intensity and frequency of the ac field and of external dc voltages. For strong driving fields, we derive, by means of perturbation theory, analytical expressions for the quasienergies of the driven oscillator system. From this analysis, we discuss the conditions for coherent destruction of tunneling (CDT) to occur as a function of detuning and field parameters. For zero detuning, and from the invariance of the Floquet Hamiltonian under a generalized parity transformation, we find analytical expressions describing the symmetry properties of the Fourier components of the Floquet states under such a transformation. By using these expressions, we show that in the vicinity of the CDT condition, the quasienergy spectrum exhibits exact crossings which can be characterized by the parity properties of the corresponding eigenvectors.