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The precise value of the g-factor in graphene is of fundamental interest for all spin-related properties and their application. We investigate monolayer graphene on a Si/SiO2 substrate by resistively detected electron spin resonance (ESR). Surprisingly, the magnetic moment and corresponding gfactor of 1.952+ − 0.002 is insensitive to charge carrier type, concentration, and mobility.

In this study, we demonstrate the possibility to tune Dirac surface states of a three-dimensional topological insulator (TI) by applying external strain to single-crystalline Bi2Se3 nanowires (NWs). The NWs were placed over 200 nm deep trenches, which leads to a significant bending, resulting in tensile strain at the bottom surface of the wire and compressive strain at its top surface. By performing low-temperature magnetotransport measurements, we were able to show that TI surfaces under compressive or tensile strain (ϵ=±0.1%) experience a significant Dirac shift of ΔE=∓30 meV as compared to relaxed surfaces. For surface states under tensile strain, an increased carrier mobility is indicated. The opportunity to externally tune the Dirac states therefore could lead to further improvement in future TI devices.

We describe a method for transferring ultra large-scale CVD-grown graphene sheets. These samples can be fabricated as large as several cm 2 and are characterized by magneto-transport measurements on SiO 2 substrates. The process we have developed is highly effective and limits damage to the graphene all the way through metal liftoff, as shown in carrier mobility measurements and the observation of the quantum Hall effect. The charge-neutral point is shown to move drastically to near-zero gate voltage after a 2-step post-fabrication annealing process, which also allows for greatly diminished hysteresis.PACS numbers: 72.80.Vp, 81.05.ue.Graphene is well-known for its desirable electrical properties, 1 and with all of the intense focus on research in the material, new applications are being constantly discovered. While graphene is known to have its best electrical properties when it is single-crystalline and suspended, 2,3 those attributes are currently not feasible for mass-produced devices. There have been very exciting developments related to improving non-suspended graphene's mobility on more exotic substrates such as hBN, 4,5 as well as improving the chemical vapor deposition (CVD) growth process for producing better quality devices with large grain sizes. 5-7 However, these developments are currently difficult to scale up and automate.On the other hand, CVD-grown graphene is still the best way to repeatably produce large areas of monolayer graphene, and SiO 2 is a well-known substrate that is already integrated into many processes from semiconductor physics to MEMS, 8,9 and beyond. Previous work has shown how to transfer large areas of CVD-grown graphene onto arbitrary substrates 10-13 and remove contaminants. 10,14 However, previous CVD-grown graphene on SiO 2 devices do not combine the desirable properties of high enough quality electrical characteristics to display the quantum Hall effect (QHE), a charge neutral point (CNP) near zero gate voltage, and a large device size, with typical finished devices being on the order of 10 µm. 15 Large-scale integration of easily manufactured, high-quality graphene devices is desirable in many different applications, such as graphene transistors, broadband optical modulators 16 and THz antennas. 17 Challenges arise when fabricating high-quality CVDgrown graphene devices, primarily due to contaminants of all kinds easily attaching to graphene. With each step,

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