Cryogenic amplifier with low input-referred voltage noise calibrated by shot noise measurement

• 来源期刊: 中国物理B（英文版）
• 关键词: cryogenic amplifier shot noise shadow evaporation tunneling junction
• 年，卷（期）: 2018,（6）
• 页码范围: 205-210
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/6/060702

摘要

A low-noise cryogenic amplifier for the bandwidth from 100 kHz to 2 MHz with commercially available components is presented.The amplifier is mounted on the cold finger of our home-made liquid helium dipstick.The input impedance of the amplifier is 2 kΩ.The input-referred voltage noise of the amplifier at approximately 2 MHz is around 1 nV/√Hz.We demonstrate the performance of the amplifier by measuring shot noise on the AI/AIOx/AI tunneling junction with resistance about 17 kΩ at liquid helium temperature.