368 research outputs found
Self-consistent model for ambipolar tunneling in quantum-well systems
We present a self-consistent approach to describe ambipolar tunneling in
asymmetrical double quantum wells under steady-state excitation and extend the
results to the case of tunneling from a near-surface quantum well to surface
states. The results of the model compare very well with the behavior observed
in photoluminescence experiments in asymmetric double quantum
wells and in near-surface single quantum wells.Comment: 10 pages, REVTeX 3.
We only die once... but from how many causes?
Analysing causes of death provides a betterunderstanding of long-term mortality trends. InFrance, the death certificates completed by physiciansgenerally mention several causes of death (2.4 onaverage in 2011). As a general rule, just one of them,the so-called underlying cause, is taken into account.As a result, the contribution of certain diseases-endocrine diseases for example-to mortality isseverely underestimated. In a context of rising lifeexpectancy where people increasingly die not from asingle cause of death but from several, it is importantto also take these contributing causes into account
Looking at Localized Excitons in Quantum Structures: A Theoretical Description
We present a theory of scanning local optical spectroscopy in quantum structures taking into account structural disorder. The calculated spatially resolved spectra show the individual spectral lines from the exciton states localized by the disordered potential as well as the quasicontinua spectra at positions close to the potential barriers in agreement with the experimental findings
Phase-bistable patterns and cavity solitons induced by spatially periodic injection into vertical-cavity surface-emitting lasers
Spatial rocking is a kind of resonant forcing able to convert a elf-oscillatory system into a phase-bistable, pattern forming system, whereby the phase of the spatially averaged oscillation field locks to one of two values differing by π. We propose the spatial rocking in an experimentally relevant system the vertical-cavity surface-emitting laser (VCSEL) and demonstrate its feasibility through analytical and numerical tools applied to a VCSEL model. We show phase bistability, spatial patterns, such as roll patterns, domain walls, and phase (dark-ring) solitons, which could be useful for optical information storage and processing purposes
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