A low-temperature device architecture for the statistical study of electrical characteristics of 256 quantum devices

摘要

Research in the field of low-temperature electronics is limited by the smallnumber of electrical contacts available on cryogenic set ups. This not onlyrestricts the number of devices that can be fabricated, but also the device andcircuit complexity. We present an on-chip multiplexing technique whichsignificantly increases the number of devices locally measurable on a singlechip, without the modification of existing fabrication or experimental set-ups.We demonstrate the operation of the multiplexer by performing electricalmeasurements of 256 quantum wires formed by split-gate devices using only 19electrical contacts on a cryogenic set-up. The multiplexer allows themeasurement of many devices and enables us to perform statistical analyses ofvarious electrical features which exist in quantum wires. We use thisarchitecture to investigate spatial variations of electrical characteristics,and reproducibility on two separate cooldowns. These statistical analyses arenecessary to study device yield and manufacturability, in order for suchdevices to form the building blocks for the realisation of quantum integratedcircuits. The multiplexer provides a scalable architecture which makes a wholeseries of further investigations into more complex devices possible.