Transport in a three-terminal graphene quantum dot in the multi-level regime

We investigate transport in a three-terminal graphene quantum dot. All nine elements of the conductance matrix have been independently measured. In the Coulomb blockade regime accurate measurements of individual conductance resonances reveal slightly different resonance energies depending on which pair of leads is used for probing. Rapid changes in the tunneling coupling between the leads and the dot due to localized states in the constrictions has been excluded by tuning the difference in resonance energies using in-plane gates which couple preferentially to individual constrictions. The interpretation of the different resonance energies is then based on the presence of a number of levels in the dot with an energy spacing of the order of the measurement temperature. In this multi-level transport regime the three-terminal device offers the opportunity to sense if the individual levels couple with different strengths to the different leads. This in turn gives qualitative insight into the spatial profile of the corresponding quantum dot wave functions.Comment: 12 pages, 6 figure

A Motion-Correction Method for Turbulence Estimates from Floating Lidars

Estimates of atmospheric turbulence performed by both fixed and floating vertically profiling, conically scanning wind lidars are affected by the measurement volume and turbulence structure, among others. We study this phenomenon by simulating the lidar measurements within synthetic fields of atmospheric turbulence. We use the simulations’ framework to assess the impact of buoy motions on turbulence estimation. Simulation results show that the buoy’s translational motions impact turbulence estimates the most. We also apply the simulation framework to analyze measurements from a floating lidar measuring nearby an offshore meteorological mast for a period of six months. The analysis of measurements is presented both without and with motion compensation. In general, we find from both simulations and measurements that the buoy motions do not impact the mean horizontal wind speed significantly, in agreement with previous studies. However, both simulations and measurements show that the standard deviation of the horizontal velocity is overestimated by the floating lidar. When we correct the measurements based on compensation factors derived from the simulations, the mean bias of the horizontal wind speed standard deviation changes from 18–19% to 5–21%, with large reductions at the first four heights closest to the surface and a slight increase at the highest vertical level

За кадры. 1980. № 60 (2284)

Для серийного производства / А. ПолиенкоНовые материалы / С. АнтоненкоОрганизуется выставка / П. ШеринСедьмая традиционная неделя студентов / Е. КатюхинаНИИ и учебный процесс / С. ЕмельяноваЛабораторный совет в действии / Ю. СивовПуть на кафедру / Т. Ю. Могилевская[...тема учебы] / Г. ЯловскаяЧтоб настоящим стал специалист / А. АлександровВ чем ключ к успеху? / Е. СергеевСтажировка углубляет знания / Л. Тигнибидина, В. ФинниковаИнженер садится за парту / Ю. И. СертаковО великом Октябре на языке эсперанто / М. ШляферНа конгрессе и симпозиуме / С. ПлатоновПриглашаем на конференциюО пионерском лагере заботиться зимой / С. КазьминаПодарок политехникам / И. Т. ЛозовскийАудитория - не место для верхней одежды / В. И. КопытовДиплом конкурса - томскому писателю / Р. ГорскаяПриглашает клуб "Заметка"Новые книги по охране природы, поступившие в НТ