[en] We present here a brief review of the Quantum Hall Effect in modulation doped heterojunctions

No abstract available

[en] Published in summary form only

[en] An electrochemically controlled polymeric heterojunction working as a memristor, i.e., having memory properties, was investigated in pulse mode, mimicking synaptic behavior of signal transmission in biological systems. Influence of parameters such as pulse duration, interval between pulses, and value of potential base level was analyzed. Learning capabilities were shown to be reversible and repeatable for both potentiation and inhibition of signal transmission. The adaptive behavior of the element was investigated and was shown to be more efficient than the dc mode

No abstract available

[en] Published in summary form only

[en] We present here recent experimental results obtained on two-dimensional semiconductor structures, namely heterojunctions and superlattices. This review, which includes both optical and transport experiments, is not exhaustive, but describes briefly some investigations which are thought to be important from the point of view of fundamental physics. (author)

[en] In this paper, it is discussed the electronic structure of semiconductor interfaces, oxidation and oxide layers, semiconductor heterojunctions and superlatices, rectifying metal-semiconductor, contacts and interface reactions. It is also discussed the role of large-scale scientific computation, as well as, the nature of theoretical models. (A.C.A.S.)

[en] The interplay between nanomorphology and efficiency of polymer-fullerene bulk-heterojunction (BHJ) solar cells has been the subject of intense research, but the generality of these concepts for small-molecule (SM) BHJs remains unclear. Here in this paper, the relation between performance; charge generation, recombination, and extraction dynamics; and nanomorphology achievable with two SM donors benzo[1,2-b:4,5-b]dithiophene-pyrido[3,4-b]-pyrazine BDT(PPTh₂)₂, namely SM1 and SM2, differing by their side-chains, are examined as a function of solution additive composition. The results show that the additive 1,8-diiodooctane acts as a plasticizer in the blends, increases domain size, and promotes ordering/crystallinity. Surprisingly, the system with high domain purity (SM1) exhibits both poor exciton harvesting and severe charge trapping, alleviated only slightly with increased crystallinity. In contrast, the system consisting of mixed domains and lower crystallinity (SM2) shows both excellent exciton harvesting and low charge recombination losses. Importantly, the onset of large, pure crystallites in the latter (SM2) system reduces efficiency, pointing to possible differences in the ideal morphologies for SM-based BHJ solar cells compared with polymer-fullerene devices. Lastly, in polymer-based systems, tie chains between pure polymer crystals establish a continuous charge transport network, whereas SM-based active layers may in some cases require mixed domains that enable both aggregation and charge percolation to the electrodes.

[en] Electron affinities are calculated in the form of linear functions of the degree of hexagonality by two different methods using the concept of band offsets in heterojunctions formed by 3C-SiC in contact with a non-cubic polytype