Holes in germanium nanowires have emerged as a realistic platform for quantum computing based on spin qubit logic. On top of the large spin−orbit coupling that allows fast qubit operation, nanowire geometry and orientation can be tuned to cancel out charge noise and hyperfine interaction. Here, we demonstrate a scalable approach to synthesize and organize Ge nanowires on silicon (100)-oriented substrates. Germanium nanowire networks are obtained by selectively growing on nanopatterned slits in a metalorganic vapor phase epitaxy system. Low-temperature electronic transport measurements are performed on nanowire Hall bar devices revealing high hole doping of ∼10 18 cm −3 and mean free path of ∼10 nm. Quantum diffusive transport phenomena, universal conductance fluctuations, and weak antilocalization are revealed through magneto transport measurements yielding a coherence and a spin−orbit length of the order of 100 and 10 nm, respectively.

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The rich and electrostatically tunable phase diagram exhibited by moiré materials has made them a suitable platform for hosting single material, multi-purpose devices. To engineer such devices, understanding electronic transport and localization across electrostatically defined interfaces is of fundamental importance. Little is known, however, about how the interplay between the band structure originating from the moiré lattice and electric potential gradients affects electronic confinement. Here, we electrostatically define a cavity across a twisted double bilayer graphene sample. We observe two kinds of Fabry–Pérot (FP) oscillations. The first, independent of charge polarity, stems from confinement of electrons between dispersive-band/flat-band interfaces. The second arises from junctions between regions tuned into different flat bands. When tuning the out-of-plane electric field across the device, we observe Coulomb blockade resonances in transport. This is an indication of strong electronic confinement. From the gate, magnetic field and source-drain voltage dependences of the resonances, we conclude that quantum dots form at the interfaces of the FP cavity. Our results constitute a first step toward better understanding interfacial phenomena in single crystal moiré devices.

Apstrakt:Sa početkom svetske finansijske krize počeo je i privredni pad Srbije, kao i slabljenje životnog standarda stanovništva što je doprinelo do smanjenja kreditne aktivnosti banaka. Ovo smanjenje se značajno odrazilo na finansijske izveštaje banaka kroz smanjenje neto rezultata (iskazani su manji, pa čak i negativni profiti) uzrokovanim uglavnom povećanim troškovima rezervacija za tzv. "loše" kredite. Kako svaki plasman nosi sa sobom određeni rizik, banka mora rezervisati određena sredstva kako bi se zaštitila od rizika. Međutim, rezervacije koštaju i direktno utičuna smanjenje finansijskog rezutltata, a samim tim i na profitabilnost banke iz ugla investitora i akcionara. U radu su prezentovani rezultati istraživanja kojim je obuhvaćeno 90% bankarskog sektora Srbije, tačnije 15 najvećih banaka po bilansnoj sumi. Prati se trend od 2007. do 2013. godine koji obuhvata period pre i tokom krize. Analizom revidiranih finansijskih izveštaja banaka dobijeni su podaci, tj. pokazatelji za merenje profitabilnosti banaka koji ukazuju na stanje pre i tokom krize, kao i na prognoze za predstojeći period. Abstract:Economic downturn of Serbia was triggered by the outbreak of the global financial crisis, and the weakening of the population's standard of living, which led to the decreased lending activity of the banks. This decrease had a significant impact on the bank's financial statements through decrease of the net results (they are lower, and even negative in some cases), which are mainly driven by the increased risk of costs for non-performing loans (NPL). As every placement carries certain level of risk, the banks need to reserve the specified amount to protect themselves against risk. On the other hand, investors and shareholders believe that such funds are costly, and have a direct negative impact on the financial results, and therefore, on the lower profitability of banks. The paper presents the results of the research, which encompasses 90% of the Serbian banking sector, i.e. 15 largest banks according to total assets. The trend from 2007 till 2013 is observed, which includes the period before and during the crisis. The data is collected by means of the analysis of the audited banking financial statements, i.e. bank profitability ratios showing the situation before and during the crisis, and the forecasts for the upcoming period. Ključne reči:banke, kriza, profitabilnost, finansijski izveštaji.