Superconducting Quantum Computing » Runs

Flux 3D spectrum: Y scale 0 to +200 uA, x scale 4500 to 5500 MHz. According to this plot +90 uA is required to tune Idler resonator to amplify at 5 GHz.

I will now try to measure noise from the JPC. Repeated Idler resonance search. Two sweetspots are around +82 uA and -161 uA for gain at 5 GHz.
Applied VNA power: -60 dBm
Pump: Off

Achieved almost 30 dB peak gain at 4.866 GHz! Average gain is about 20 dB across 10 MHz bandwidth.
Found next parameters:
Current bias: -0.1626 mA
Pump freq: 14.0324 GHz
Pump power setting: 16.9 dBm
VNA power setting: -90 dBm

Some results from JPC noise measurement.
Conditions:
Spectrum analyzer resolution bandwidth = 1 Hz, Span = 0 Hz
HEMT plate temperature = 2.43 K
Mixing chamber temperature = 12.6 mK
..\redmine\runs\DR1_run_4\python_measurements\quantum_amp_yale\noise_measurement

Spectrum of JPC Vacuum noise Amplification

We made additional cooldown with slightly different connection of the JPC. Its input is now connected with a superconducting cable to the 20 dBm attenuator located on the Still Flange, so the noise of the 990 mK would be aplified by the JPC.
Just finished flux sweep to determine the sweetspot. Looks like the total picture shifted significantly from the previous run.