Quantum calculations on quantum dots in semiconductor microcavities. Part I

Quantum calculations on quantum dots in semiconductor microcavities. Part III

“…In addition, when considering the effect of the coherence loss, the role of the phonon reservoir was evaluated incorrectly; specifically, the combined photon phonon scattering in QDs was ignored. Meanwhile, as follows from the recent experiments [1], these mechanisms determine the lifetime of the excited state of a QD detuned from resonance with the MC and their rate exceeds by far the rate of dissipation caused by direct phonon emis sion calculated in [4][5][6] using Fermi's golden rule. This places in question the reliability of the proposed off resonance two photon schemes in which the low population of the auxiliary QD levels and MC modes guaranteed the low qubit relaxation rate.…”

“…How can two qubit gates be implemented in such a system? As we know, the cavity field affects, to an extent, the QD evolution if their fre quencies are sufficiently close [1,2]. Therefore, tuning two or more arbitrary QDs in resonance with the MC mode, one can organize the indirect interaction between their internal degrees of freedom, which code quantum information, by means of the exchange by an energy quantum between these QDs through the MC mode.…”

“…The Hamiltonian describing the coherent interac tion of the set of N of two qubit QDs and a single mode MC in the rotating wave approximation is the natural generalization of the Jaynes-Cummings model and is called the Tavis-Cummings Hamilto nian (1) where ω c is the MC mode frequency, ω a,j is the fre quency of the exciton transition in the jth QD, g j is the coefficient of the interaction between the jth QD and the MC mode, and and are the opera tors of the creation and annihilation of the excitation quantum in the MC (QD). This expression can be added to the term that reflects the effect of external control fields and non Markovian phonon modes on the system [1].…”

“…This expression can be added to the term that reflects the effect of external control fields and non Markovian phonon modes on the system [1]. The Markovian dissipative effects are introduced, as usual, in the description of the system dynamics with the use of the Lindblad formalism through a set of phenomenological decay rates, such as rate κ of the phonon escape from the MC and rates γ j , γ d, j and γ r, j of spontaneous emission, dephasing, and photon phonon relaxation of the jth QD, respec tively.…”

“…In the first [1] and second [2] parts of our review, we got acquainted with the physical fundamentals of the solid state nanosystem comprising a semiconductor quantum dot (QD) interacting with a photon field of the high Q optical microcavity (MC). We have seen that the theoretical models and experimental data indicate the similarity of this hybrid structure with another system quite popular in quantum optics, spe cifically, the atom placed in a single mode Fabry-Perot cavity.…”