Dynamical bistability in quantum-dot structures: Role of Auger processes

Abstract

Bistability in quantum-dot structures is examined by a drift-diffusion model in combination with electron capture and emission processes. Our simulations provide a dynamic scenario with extremely long switching times of the order of months and the results are in good agreement with the experimental findings of Yusa and Sakaki ͓Appl. Phys. Lett. 70, 345 ͑1997͔͒. The analysis of the data supports the importance of Auger capture processes for quantum dots.

Theory of Nonlinear Transport for Ensembles of Quantum Dots

“…Assuming that the generation-recombination kinetics in the QDs is dominated by the Auger effect, the low densities in the regions around the QDs provide an extremely slow kinetics, resulting in an effective bistability for bias sweep up and down of the order of an hour, see the result in Fig. 2, which is in excellent agreement with the experiment [20]. Calculated bistability for the diode structure of Ref.…”

“…While the stationary density Ns of the 2D electron gas has a unique solution, the slow kinetics of Auger capture and emission provides effective bistability on the time scale of an hour. (from [20])…”

Coulomb Damped Relaxation Oscillations in Semiconductor Quantum Dot Lasers

“…These have to be captured into the bound QD states before the laser transition can take place. Since in the lasing regime, the WL carrier density is very high, the capture processes are dominated by Coulomb scattering (nonlocal Auger recombination) [23], [25], [26], which is also supported by the modeling of QD transport experiments [27], [28]. Our approach also includes the electron-phonon scattering for the cooling process in the WL, but neglects it for scattering into the QD states.…”

Localized charge bifurcation in the coupled quantum dots

“…Intrinsic bistabilities in different tunneling structures were widely studied experimentally and theoretically. Obtained results provide evidence for various molecular [1], [2] and QDs [29], [22], [23], [24] switching effects apparent in I-V characteristics due to the bistabilities in the tunneling current flowing through the system. It was experimentally demonstrated [1], [2] that switching strongly depends on the choice of contacts, substrates and can be observed even for simple molecules.…”