2026-06-08T04:02:07Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/346292023-08-27T17:09:48Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Carreño Sánchez, Fernando author Antón Revilla, Miguel Ángel author Melle Hernández, Sonia author Gómez Calderón, Óscar author Cabrera Granado, Eduardo author Cox, Joel author Singh, Mahi R. author Egatz-Gómez, Ana author 2014 A scheme for terahertz (THz) generation from intraband transition in a self-assembled quantum dot (QD) molecule coupled to a metallic nanoparticle (MNP) is analyzed. The QD structure is described as a three-level atom-like system using the density matrix formalism. The MNP with spherical geometry is considered in the quasistatic approximation. A femtosecond laser pulse creates a coherent superposition of two subbands in the quantum dots and produces localized surface plasmons in the nanoparticle which act back upon the QD molecule via dipole-dipole interaction. As a result, coherent THz radiation with a frequency corresponding to the interlevel spacing can be obtained, which is strongly modified by the presence of the MNP. The peak value of the terahertz signal is analyzed as a function of nanoparticle's size, the MNP to QD distance, and the area of the applied laser field. In addition, we theoretically demonstrate that the terahertz pulse generation can be effectively controlled by making use of a train of femtosecond laser pulses. We show that by a proper choice of the parameters characterizing the pulse train a huge enhancement of the terahertz signal is obtained. 0021-8979 10.1063/1.4863781 https://hdl.handle.net/20.500.14352/34629 http://dx.doi.org/10.1063/1.4863781 http://scitation.aip.org/content/aip/journal/jap/115/6/10.1063/1.4863781 Plasmon-enhanced terahertz emission in self-assembled quantum dots by femtosecond pulses