Task #21977

Yale Quantum Limited Amplifier

Added by Daniil Frolov about 2 years ago. Updated almost 2 years ago.

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Turn on the amplifier.

Capture4322252019.JPG (38.6 KB) Capture4322252019.JPG Daniil Frolov, 02/25/2019 04:32 PM
Capture4362252019.JPG (33.5 KB) Capture4362252019.JPG Daniil Frolov, 02/25/2019 04:36 PM
IdlerVScurrent3620191010.png (75 KB) IdlerVScurrent3620191010.png Daniil Frolov, 03/06/2019 10:10 AM
JPCGain_2090306.jpg (139 KB) JPCGain_2090306.jpg Daniil Frolov, 03/06/2019 10:57 AM
362019107.png (173 KB) 362019107.png Daniil Frolov, 03/06/2019 01:08 PM
JPC_pump_on_bias_on_gain.png (81 KB) JPC_pump_on_bias_on_gain.png Roman Pilipenko, 03/06/2019 06:31 PM
jpc_flux_sweep432019509.JPG (147 KB) jpc_flux_sweep432019509.JPG Daniil Frolov, 04/03/2019 05:38 PM


#1 Updated by Daniil Frolov about 2 years ago

We are now preparing quantum amplifier. Found optimal receiver delay to observe Idler resonance as 123.8 ns, center freq 5 GHz, span 2 GHz.

#2 Updated by Daniil Frolov about 2 years ago

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.

#3 Updated by Daniil Frolov about 2 years ago

For reference: quantum amplifier is ON now and centered around 5 GHz, gain at 5 GHz is ~15 dB.

#4 Updated by Daniil Frolov about 2 years ago

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

#5 Updated by Daniil Frolov about 2 years ago

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

#6 Updated by Daniil Frolov about 2 years ago

Some results from JPC noise measurement.
Spectrum analyzer resolution bandwidth = 1 Hz, Span = 0 Hz
HEMT plate temperature = 2.43 K
Mixing chamber temperature = 12.6 mK

#7 Updated by Roman Pilipenko about 2 years ago

Spectrum of JPC Vacuum noise Amplification

#8 Updated by Daniil Frolov about 2 years ago

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.

#9 Updated by Daniil Frolov almost 2 years ago

  • Status changed from New to Closed

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