Related papers: Realization of 5 h/e^2 with graphene quantum Hall …
Series connection of four quantum Hall effect (QHE) devices based on epitaxial graphene films was studied for realization of a quantum resistance standard with an up-scaled value. The tested devices showed quantum Hall plateaux RH,2 at…
Precision quantum Hall resistance (QHR) measurements were performed on large-area epitaxial graphene device at low magnetic fields (B = 2 T - 8 T) at temperature T = 1.5 K. Hall resistance was measured using Cryogenic Current Comparator…
We report development of a quantum Hall resistance standard accurate to a few parts in a billion at 300 mK and based on large area epitaxial graphene. The remarkable precision constitutes an improvement of four orders of magnitude over the…
Quantum Hall effect (QHE) devices based on epitaxial graphene films grown on SiC were fabricated and studied for development of the QHE resistance standard. The graphene-metal contacting area in the Hall devices has been improved and…
The quantum Hall effect (QHE) is a cornerstone in the new International System of Units (SI), wherein the base units are derived from seven fundamental constants such as Planck's constant h and elementary charge e. Graphene has…
We report high-precision resistance measurements on quantum Hall resistance devices fabricated from uniform epitaxial graphene grown by propane-hydrogen chemical vapor deposition on a two-inch silicon carbide substrate. Through molecular…
We show that quantum resistance standards made of transferred graphene reach the uncertainty of semiconductor devices, the current reference system in metrology. A large graphene device (150 \times 30 \mum2), exfoliated and transferred onto…
We have performed a metrological characterization of the quantum Hall resistance in a 1 $\mu$m wide graphene Hall-bar. The longitudinal resistivity in the center of the $\nu=\pm 2$ quantum Hall plateaus vanishes within the measurement noise…
The quantum Hall effect (QHE) theoretically provides a universal standard of electrical resistance in terms of the Planck constant $h$ and the electron charge $e$. In graphene, the spacing between the lowest discrete energy levels occupied…
We demonstrate quantum Hall resistance measurements with metrological accuracy in a small cryogen-free system operating at a temperature of around 3.8K and magnetic fields below 5T. Operating this system requires little experimental…
Precision measurements of the quantum Hall resistance with alternating current (ac) in the kHz range were performed on epitaxial graphene in order to assess its suitability as a quantum standard of impedance. The quantum Hall plateaus…
Replacing GaAs by graphene to realize more practical quantum Hall resistance standards (QHRS), accurate to within $10^{-9}$ in relative value, but operating at lower magnetic fields than 10 T, is an ongoing goal in metrology. To date, the…
The half-integer quantum Hall effect in epitaxial graphene is compared with high precision to the well known integer effect in a GaAs/AlGaAs heterostructure. We find no difference between the quantised resistance values within the relative…
We report the first observation of the quantum Hall effect in epitaxial graphene. The result described in the submitted manuscript fills the yawning gap in the understanding of the electronic properties of this truly remarkable material and…
A mathematical approach is adopted for optimizing the number of total device elements required for obtaining high effective quantized resistances in graphene-based quantum Hall array devices. This work explores an analytical extension to…
Quantized magnetotransport is observed in 5.6 x 5.6 mm^2 epitaxial graphene devices, grown using highly constrained sublimation on the Si-face of SiC(0001) at high temperature (1900 {\deg}C). The precise quantized Hall resistance of Rxy =…
It is theoretically possible to combine several Hall bars in arrays to define new quantum standards with perfectly quantized resistance values. We have thus, for the first time, developed and fabricated novel Quantum Hall Array Resistance…
We have demonstrated the millimeter-scale fabrication of monolayer epitaxial graphene $p-n$ junction devices using simple ultraviolet photolithography, thereby significantly reducing device processing time compared to that of electron beam…
In this work, limiting factors for developing metrologically useful arrays from epitaxial graphene on SiC are lifted with a combination of centimeter-scale, high-quality material growth and the implementation of superconducting contacts.…
Measurements of fractional multiples of the {\nu}=2 plateau quantized Hall resistance (R_H {\approx} 12906 {\Omega}) were enabled by the utilization of multiple current terminals on millimetre-scale graphene p-n junction devices fabricated…