Comparison of Multiple Methods for Obtaining PΩ Resistances with Low Uncertainties.

Capabilities for high resistance determinations are essential for calibration of currents below 1 pA, as typically requested in several applications, including semiconductor device characterization, single electron transport, and ion beam technologies. This need to calibrate low currents warrants the expansion of accessible values of high resistance. We present several methods for measuring resistances on the PΩ scale, namely potentiometry, dual source bridge measurements, and teraohmmeter usage, all of which are subsequently compared to theoretical calculations.

Towards epitaxial graphene p-n junctions as electrically programmable quantum resistance standards.

We report the fabrication and measurement of top gated epitaxial graphene p-n junctions where exfoliated hexagonal boron nitride (h-BN) is used as the gate dielectric. The four-terminal longitudinal resistance across a single junction is well quantized at the von Klitzing constant [Formula: see text] with a relative uncertainty of 10. After the exploration of numerous parameter spaces, we summarize the conditions upon which these devices could function as potential resistance standards.

Graphene Devices for Tabletop and High-Current Quantized Hall Resistance Standards.

We report the performance of a quantum Hall resistance standard based on epitaxial graphene maintained in a 5-T tabletop cryocooler system. This quantum resistance standard requires no liquid helium and can operate continuously, allowing year-round accessibility to quantized Hall resistance measurements. The = 2 plateau, with a value of /2, also seen as , is used to scale to 1 kΩ using a binary cryogenic current comparator (BCCC) bridge and a direct current comparator (DCC) bridge.

Low-Ohmic Resistance Comparison: Measurement Capabilities and Resistor Traveling Behavior.

The low-ohmic resistance measurement capabilities of the Van Swinden Laboratorium, National Institute of Standards and Technology, and the Federal Office of Metrology (METAS) were compared using a set of resistors with values 100 mΩ, 10 mΩ,1 mΩ, and 100 Ω, respectively. The measurement results of the three laboratories agree extremely well within the respective measurement uncertainties with the comparison reference value. Careful transport of the resistors was crucial for achieving this result.