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Kondo and Fano effect in side attached double quantum-dot molecule
Lara,Gustavo A.; Orellana,Pedro A.; Yáñez,Julio M.; Anda,Enrique V.Electron tunneling through a double quantum dot molecule side attached to a quantum wire, in the Kondo regime, is studied. The mean-field finite-U slave-boson formalism is used to obtain the solution of the problem. We investigate the many body molecular Kondo state and its interplay with the inter-dot antiferromagnetic correlation as a function of the parameters of the system.
Polaron effect on Raman scattering in semiconductor quantum dots
Vasilevskiy, Mikhail; Miranda, R. P.; Anda, Enrique; Makler, SergioStrong coupling of a confined exciton to optical phonons in semiconductor quantum dots (QDs) leading to the formation of a polaron is considered for a model system including two lowest exciton states and several optical phonon modes. Both intra- and inter-level terms are taken into account. The Hamiltonian has been exactly diagonalized including a finite number of phonons allowed for each mode, large enough to ...
Electron-phonon interaction effects in semiconductor quantum dots: a non-pertur...
Vasilevskiy, Mikhail; Anda, Enrique; Makler, SergioMultiphonon processes in a model quantum dot (QD) containing two electronic states and several optical phonon modes are considered by taking into account both intra- and nterlevel terms. The Hamiltonian is exactly diagonalized, including a finite number of multiphonon processes large enough to guarantee that the result can be considered exact in the physically important energy region. The physical properties a...
A quantum formalism for a terahertz acoustic laser
Camps Rodríguez,Ihosvany; Makler,Sergio Saul; Anda,Enrique VictorianoThe aim of this work is to improve the study of a phonon laser (saser) proposed by us several years ago[1]. This is a device capable to generate an intense coherent beam of acoustical phonons. Our acoustic laser consists in a double barrier heterostructure tailored such the energy difference between the ground and the first excited state in the well is close to the energy of the LO phonon. The electrons are dir...
The effect of size dispersion on the optical absorption of a system of semicond...
Vasilevskiy, Mikhail; Akinkina, Evgenia; Paula, Ana Maria de; Anda, EnriqueThe linear optical absorption of an ensemble of semiconductor quantum dots randomly positioned in an insulating matrix is studied theoretically and experimentally for the CdTe/glass system. The calculation of the effective dielectric function of the system, whose imaginary part determines the absorption, is based on a modified Maxwell–Garnett formalism using a diagram technique to calculate the average renormal...
A source of terahertz coherent phonons
Makler, Sergio; Vasilevskiy, Mikhail; Tuyarot, Diana; Weberszpil, José; Anda, Enrique; Pastawski, HoracioResonant tunnelling in a double-barrier heterostructure (DBHS) designed in order to produce an intense coherent emission of phonons is studied theoretically. Thisemission is achieved when the energy difference between the first excited level and the ground state in the well is close to the LO-phonon energy. The LO phonons emitted during the electron transition decay into a pair of (fLO and TA) phonons that leav...
Effective dielectric response of semiconductor composites
Vasilevskiy, Mikhail; Anda, EnriqueUsing a previously proposed diagrammatic approach for the calculation of the renormalized polarizability of spherical inclusions in a homogeneous matrix we obtain an effective dielectric response of a composite of nonpercolating inclusions taking into account a continuous distribution of sizes of the spheres. We apply this theory to semiconductor-doped glasses ~SDG! calculating both the electron and phonon resp...
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