Abstract: A low-magnetic-field gallium arsenide Quantum Hall Resistance sample can reproduce a Quantum Hall Resistance effect under lower magnetic field conditions, and has a wider plateau width of the quantum resistance sample being equal or greater than 0.6 T, and the magnetic field condition corresponds to the central magnetic field of the plateau being 2 between 7 T and 8 T. The sample includes a GaAs heterojunction material, the GaAs heterojunction material has a seven-layer structure including first to seventh layers sequentially stacked upwards and bonded to a surface of a GaAs substrate. The first layer is a GaAs isolation layer, the second layer is GaAs/AlGaAs superlattice layer, the third layer is high-purity GaAs layer, the fourth layer is a two-dimensional electron gas layer, the fifth layer is an undoped AlxGa1-xAs isolation layer, the sixth layer is a Si-doped AlxGa1-xAs layer, and the seventh layer is a GaAs surface layer.

Abstract: A four-terminal-pair AC quantum resistance dissemination bridge and related methods are provided. The bridge includes: a supply transformer IVD1, a Kelvin branch A1, a Wagner branch A0, the first and second current sources A2, A3, an injection inductive voltage divider A4, a ratio transformer IVD2, the first and second four-terminal AC resistor connection points Z1, Z2, chokes H, and null indicators D. An isolated inductive winding LO is wound along the ratio transformer IVD2 and supplies excitation current to primary winding of injection inductive voltage divider A4 to avoid the mutual influence among various balance networks and rapid balance of the bridge can be realized. By changing turn ratio of primary winding L3 and secondary winding L4 of the second inductive voltage divider T2, the phase shift can be realized through only one set of capacitors for imaginary part error compensation, the bridge with multiple frequency points can be obtained.

Abstract: A four-terminal-pair AC quantum resistance dissemination bridge and related methods are provided. The bridge includes: a supply transformer IVD1, a Kelvin branch A1, a Wagner branch A0, the first and second current sources A2, A3, an injection inductive voltage divider A4, a ratio transformer IVD2, the first and second four-terminal AC resistor connection points Z1, Z2, chokes H, and null indicators D. An isolated inductive winding LO is wound along the ratio transformer IVD2 and supplies excitation current to primary winding of injection inductive voltage divider A4 to avoid the mutual influence among various balance networks and rapid balance of the bridge can be realized. By changing turn ratio of primary winding L3 and secondary winding L4 of the second inductive voltage divider T2, the phase shift can be realized through only one set of capacitors for imaginary part error compensation, the bridge with multiple frequency points can be obtained.