Welcome to my workshop! Once situated in my bedroom, to maintain many happy years of marriage you can now find it in my basement. For nearly 15 years a Tek 475 was at the heart of this bench, but sadly, my love for electronics has outlived its 70’s era CRT. A scopemeter now sits in its place, but I desperately miss the performance of a dedicated scope. You will also find on my bench a pair of sweep/function generators sold for parts on eBay nearly 15 years ago. With a little love and a lot of caps they can now get the job done. In blue is my converted computer noise generator...I mean power supply. My ever-growing collection of parts surrounds my little nest and everything is easy to find. My wife’s old PC makes a great logic analyzer.
I find it easiest to design boards and write code on my adjacent desk. To its side you will see my 3D printer, hooked up to some home brew filament dry boxes (temperature/humidity data logged, of course) and my 3D printed table saw for cutting PCB panels.
A year ago, I finished a postdoc fellowship studying quantum-dot spin qubits and was looking to start my own lab when hiring freezes temporarily left me unemployed. While electronics projects have always been an outlet for me, I missed working on problems that I thought were important, so I set out to tackle projects that benefit spin qubits (and likely other labs). In general, this means developing ultra-low-noise instrumentation. Spin qubits typically use energy scales of 10’s of ueV, so even microvolts of noise degrades performance.
In the past months I designed transimpedance amplifiers for measuring the tiny currents coming out of qubit devices (100 pA signals with a bandwidth of 100 kHz). I have built high-precision (20 bit) D to A converters with noise characteristics suitable for spin qubit research (8-channel boards visible on the bench). Now, I’m turning my attention to an RF (10 MHz) amplifier designed to work at cryogenic temperatures and a variable-gain, low-noise voltage preamplifier with programmable filters.