Simulation studies of photon-assisted quantum transport

Article

关键词: DEPENDENT SCHRODINGER-EQUATION;    RESONANT TUNNELING DIODES;    POINT-CONTACT;    RADIATION DETECTION;    TIME;    IONIZATION;    OSCILLATIONS;    FREQUENCIES;    SCATTERING;    JUNCTIONS;   

DOI  :  10.1103/PhysRevB.54.7987

来源: SCIE

【 摘 要 】

Direct numerical simulations were performed to investigate conditions for the strong effects of photon-assisted quantum transport. Transmission probabilities of incident electrons as Gaussian wave packets were calculated for single- and double-barrier structures irradiated by electromagnetic fields that were focused within a finite region xi(ac). When the period of the ac electromagnetic field is short compared with the time tau(xi ac), which is the traversal time of the electrons in the region of the applied ac field, the transmission probability can be affected by photon emission and photon absorption. The magnitude of these effects strongly depends on the width xi(ac) and the bound-state character of the electrons. These dependences can be understood from the selection rule, which results from the momentum conservation of the electron and photon system. Consequently, we have shown that photon-assisted transport over a single barrier is difficult to achieve in two-dimensional electron-gas devices due to the relatively long screening length. We have demonstrated, however, that the photon-assisted process is significantly enhanced in double-barrier devices due to quasibound-to-extended-state transitions.

【 授权许可】

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