A pedagogical experimental setup to measure quantum transport

We designed and built a compact device capable of measuring electronic transport in atomic-sized contacts. This experimental setup is based on the break-junction (BJ) approach. According to the samples used as electrodes, we named the instrument a Surface-Tip Break Junction. Our instrument, like a scanning tunnelling microscope in the BJ configuration, can measure the quantum transport in atoms captured by electrodes. In our case, to measure this transport, we included a homemade I-V converter, a low-cost oscilloscope, and a mobile phone that functions as a data acquisition system. Moreover, we developed a protocol to analyse the digitized data obtained from the oscilloscope. This low-cost pedagogical setup offers the possibility of implementation in undergraduate and graduate laboratories.