A programmable quantum current generator based on the application of Ohm’s law to quantum voltage and resistance standards has demonstrated a realization of the ampere from the elementary charge with a 10⁻⁸ relative uncertainty (Brun-Picard etal 2016 Phys. Rev. X 6 041051). Here, we report on improvements of the device leading to a noise reduction of the generated quantized current. The improved quantum current generator is used to calibrate different ammeters with lower measurement uncertainties. Besides, measurements of its quantized current using a calibrated ultrastable low-noise current amplifier have shown that the realizations of the ampere at PTB (Physikalisch-Technische Bundesanstalt) and LNE (Laboratoire national de Mtrologie et d’essais) in the range 50 μA agreed to −3.7 parts in 10⁷ with a combined standard uncertainty of 3.1 parts in 10⁷ (coverage factor k _c = 1).

基于将欧姆定律应用于量子电压和电阻标准的可编程量子电流发生器已经展示了从具有 10 ^-8相对不确定性的基本电荷实现的安培（Brun-Picard et al 2016 Phys. Rev. X 6041051)。在这里，我们报告了设备的改进，从而降低了生成的量化电流的噪声。改进的量子电流发生器用于校准具有较低测量不确定性的不同电流表。此外，使用校准的超稳定低噪声电流放大器对其量化电流的测量表明，在 PTB (Physikalisch-Technische Bundesanstalt) 和 LNE (Laboratoire national de Mtrologie et d'essais) 的安培实现在 50 μA 范围内是一致的10 ⁷中的-3.7 份，组合标准不确定度为 10 ⁷中的 3.1 份（覆盖因子k _c = 1）。