Low-Noise Current Source for Dilution Refrigerator Heat Switches
Sevenne, Daniel (2017)
Sevenne, Daniel
Metropolia Ammattikorkeakoulu
2017
All rights reserved
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-201705107465
https://urn.fi/URN:NBN:fi:amk-201705107465
Tiivistelmä
Low-temperature physics, or cryogenics, has fast returned to the forefront of technological advancement in recent years with the advent of the quantum computing processor. This experimental technology, which is still under development to discover a more stable outcome, requires extremely low temperatures in order to function properly.
The need for a noiseless environment is obvious in this case, since at the lowest temperatures, even the slightest interference can throw off measurements wildly. Working with wiring and electronics, this thesis project aimed to make a cleaner current source for resistive heaters which are used to control thermally isolating heat switches within the devices, and also to literally heat up the device after tests have been performed. A prototype was developed based on a simple clean current source topology found in a white paper, and modified to fit the needs of the specific application.
After multiple iterations, debugging and reworking, the current source prototype was found to function as planned. LTSpice simulations done alongside the physical implementation agreed with breadboard circuit testing results, and a schematic and layout were created. The prototype printed circuit board is now ordered, and components will be hand soldered in place before further testing, and then will be tested again in the dilution refrigerators themselves.
The need for a noiseless environment is obvious in this case, since at the lowest temperatures, even the slightest interference can throw off measurements wildly. Working with wiring and electronics, this thesis project aimed to make a cleaner current source for resistive heaters which are used to control thermally isolating heat switches within the devices, and also to literally heat up the device after tests have been performed. A prototype was developed based on a simple clean current source topology found in a white paper, and modified to fit the needs of the specific application.
After multiple iterations, debugging and reworking, the current source prototype was found to function as planned. LTSpice simulations done alongside the physical implementation agreed with breadboard circuit testing results, and a schematic and layout were created. The prototype printed circuit board is now ordered, and components will be hand soldered in place before further testing, and then will be tested again in the dilution refrigerators themselves.