We investigate the magneto-transport properties of epitaxial graphene single-layer on 4H-SiC(0001), grown by atmospheric pressure graphitization in Ar, followed by H2 intercalation. We directly demonstrate the importance of saturating the Si dangling bonds at the graphene/SiC(0001) interface to achieve high carrier mobility. Upon successful Si dangling bonds elimination, carrier mobility increases from 3 000 cm2V−1s−1 to >11 000 cm2V−1s−1 at 0.3 K. Additionally, graphene electron concentration tends to decrease from a few 1012 cm−2 to less than 1012 cm−2. For a typical large (30 × 280 μm2) Hall bar, we report the observation of the integer quantum Hall states at 0.3 K with well developed transversal resistance plateaus at Landau level filling factors of ν = 2, 6, 10, 14… 42 and Shubnikov de Haas oscillation of the longitudinal resistivity observed from about 1 T. In such a device, the Hall state quantization at ν = 2, at 19 T and 0.3 K, can be very robust: the dissipation in electronic transport can stay very low, with the longitudinal resistivity lower than 5 mΩ, for measurement currents as high as 250 μA. This is very promising in the view of an application in metrology.

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Absrrmf -Innovntive,open magnet designs for Magnetic Resonance Imaging (MRI) of p r t s of hiimmn body hnve been recently proposed. 'I'lisse open configuritlons require notrl)le skill in the design phase to obtain sntisfnctory perfnrninnre i n terms of compnctness niid field homogenelty: optimization techniques thus seems adequate to m i s t the designer of such devices. A novel o~itinilxation sclicmc, based on n gciietlc nlgorithm (CA) hms been Implcmctited fnr the resolution nf this problem, Tlic G h seems well suited For this mpplicitlons thanks to Its abillty in exploring the whole desip parameters sprcr, iiot bceii implemented, namely tlonting point pnrnmctrr representation, lntrodiiction of R direciionn! miitfitlon opcrntor and ndiptive probability of operators rctioii.

An effective approach to the optimal design of electromagnetic devices should take into account the effect of mechanical tolerances on the actual devices performance. A possible approach could be to match a Pareto optimality study with a Monte Carlo analysis by randomly varying the constructive parameters. In this paper it is shown how such an analysis can be used to allow an expert designer to select among different Pareto optimal designs.