Extended Data Fig. 1: Experimental setup.
From: Operation of a silicon quantum processor unit cell above one kelvin
The device measured is identical to the one described in ref. 11. It is fabricated on an isotopically enriched 900-nm-thick 28Si epilayer12 with 800 ppm residual concentration of 29Si using multi-layer gate-stack silicon MOS technology39,40. Rechargeable isolated voltage source modules (SIM928 from Stanford Research System, SRS, mounted in SRS SIM900 mainframes) are used to supply all our d.c. (DC) voltages, and a LeCroy ArbStudio 1104 arbitrary waveform generator (AWG) is combined with the d.c. voltages through resistive voltage dividers, with 1/5 division for the d.c. and 1/25 for the AWG inputs. The resistance of the voltage dividers in combination with the capacitance of the coaxial cables limits the AWG bandwidth to ~5 MHz. Filter boxes with lowpass filtering (100 Hz for d.c. lines and 80 MHz for fast lines) and thermalization are mounted on the mixing chamber (MC) plate. Shaped microwave (MW) pulses are delivered by an Agilent E8267D vector signal generator, employing its own internal AWG for in-phase/quadrature (IQ) modulation. There are two d.c. blocks and two attenuators along the microwave line, as indicated in the schematic. The SET sensor current signal is amplified by a FEMTO DLPCA-200 transimpedance amplifier and an SRS SIM910 JFET isolation amplifier with gain of 100, before passing an SRS SIM965 lowpass filter and finally being acquired by an Alazar ATS9440 digitizer. The SpinCore PBESR-PRO-500 pulse generator acts as the master trigger source for all other instruments. The device sits inside an Oxford Kelvinox 100 wet dilution refrigerator with base temperature TMC = 40 mK. The superconducting magnet is powered by an American Magnet Inc. AMI430 power supply. CH1–CH4, physical channel input/output 1–4 from the instruments.
