A macroscopic mass from quantum mechanics in an integrated approach

The revision of the International System of Units (SI) on May 20th, 2019, has enabled new improved experiments to consolidate and simplify mechanical and quantum electrical metrology. Here, we present the direct measurement between a macroscopic mass and two quantum standards in a single experiment, in which the current used to levitate a mass passes through a graphene quantum Hall standard. The Josephson effect voltage is compared directly to the resulting quantum Hall effect voltage. We demonstrate this measurement with the use of graphene quantum Hall arrays for scaling in resistance with improved uncertainty and higher current level. The SI units, some of which were initially defined using physical objects, have come to rely on more stable and reproducible forms of measurement in order to improve accuracy. Here, the authors integrate a quantum Hall resistance array and programmable Josephson voltage standard in a circuit to quantum mechanically determine current and, via a Kibble balance, measure the unit of mass as well.