VHF Josephson Arbitrary Waveform Synthesizer, IEEE Transactions On Applied Superconductivity
National Institute of Standards and Technology
@usgov.national_institute_of_standard_vhf_josephson_arbitrary_e6c3b193
National Institute of Standards and Technology
@usgov.national_institute_of_standard_vhf_josephson_arbitrary_e6c3b193
These data will appear in [1]. The abstract for that paper is given below:We report on the design, fabrication, and measurement of a Very High Frequency band Josephson Arbitrary Waveform Synthesizer (VHF-JAWS) at frequencies from 1kHz to 50.05MHz. The VHF-JAWS chip is composed of a series array of 12,810 Josephson junctions (JJs) embedded in a superconducting coplanar waveguide. Each JJ responds to a pattern of current pulses by creating a corresponding pattern of voltage pulses, each with a time-integrated area related to fundamental constants as $ extit{ extbf{h/2e}}$. The pulse patterns are chosen to produce quantum-based single-tone voltage waveforms with an open-circuit voltage of 50mVrms (\mbox{-19.03dBm} output power into 50$\Omega$ load impedances) at frequencies up to 50.05MHz, which is more than twice the voltage that has been generated by previous RF-JAWS designs at 1GHz. The VHF-JAWS is "quantum-locked", that is, it generates one quantized output voltage pulse per input current pulse per JJ while varying the dc current through the JJ array by at least 0.4mA and the amplitude of the bias pulses by at least 10%. We use the large bias pulse quantum-locking range to investigate one source of error in detail: the direct feedthrough of the current bias pulses into the DUT at VHF frequencies. We reduce this error by high-pass filtering the current bias pulses and measure the error as a function of input pulse amplitude using two techniques: by measuring small changes over the quantum-locking range and by passively attenuating the input pulse amplitude so that the nonlinear JJs no longer generate voltage pulses while the error is only linearly scaled.
Organization: National Institute of Standards and Technology
Last updated: 2024-03-12T23:56:27.774396
Tags: digital-analog-conversion, josephson-junction-arrays, power-measurement-standards, signal-synthesis, superconducting-integrated-circuits, superconducting-microwave-devices
CREATE TABLE fig3_transfer_function (
"frequency_dependence_of_the_measured_digitizer_voltage_b581b734" VARCHAR -- Frequency Dependence Of The Measured Digitizer Voltage Generated By The VHF-JAWS From 1 KHz To 50.05 MHz (transfer Function Freq (Hz)). The Rms Voltage (transfer Function Voltage (mV)) Measured Across The 50 Ohm Input Impedance Of The Digitizer Is Used To Calculate The Output Power (transfer Function Power (dBm)). This Data Was Taken At An RF AWG Bias Pulse Amplitude Of 0.43 And A Dc Bias Current Of Zero.,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2
);CREATE TABLE fig5_bottom_dc_qlr (
"dc_bias_current_qlrs_the_first_three_columns_are_the_f_f42f2b66" VARCHAR -- DC Bias Current QLRs. The First Three Columns Are The Flattened Data For A Density Plot Of The Total Harmonic Distortion (dBc) Versus DC Offset Current (mA) For Waveform Frequencies Up To 50.05 MHz. The Last Three Columns Are Data For The Black Dashed Scatter Plot, Which Denotes The QLR Margin Minimum (mA) And QLR Margin Maximum (mA). All Data Is Taken At A Default RF AWG Pulse Amplitude (0.43 AWG V (p-p)).,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2,
"unnamed_3" VARCHAR -- Unnamed: 3,
"unnamed_4" VARCHAR -- Unnamed: 4,
"unnamed_5" VARCHAR -- Unnamed: 5
);CREATE TABLE fig5_top_dc_qlr (
"dc_bias_current_qlrs_rms_voltage_magnitude_mv_vs_dc_of_093a1b48" VARCHAR -- DC Bias Current QLRs. RMS Voltage Magnitude (mV) Vs DC Offset (mA) 50 KHz, 150 KHz, 5.5 MHz, 15.05 MHz, 30.05 MHz, And 50.05 MHz Waveforms. The Rms Voltage Values For The 30.05 MHz Tone Shown Here And In The Figure Are +5.5 MV Higher Than The Measured Values. This Addition Was Included For Visual Clarity.,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2
);CREATE TABLE fig6_bottom_pulse_amp_qlr (
"pulse_amplitude_qlrs_total_harmonic_distortion_dbc_vs__a8040b12" VARCHAR -- Pulse Amplitude QLRs. Total Harmonic Distortion (dBc) Vs Programmed Peak-to-peak Amplitude (AWG V (p-p)) For 50 KHz, 150 KHz, 5.5 MHz, 15.05 MHz, 30.05 MHz, And 50.05 MHz Waveforms.,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2
);CREATE TABLE fig6_top_pulse_amp_qlr (
"pulse_amplitude_qlrs_rms_voltage_magnitude_mv_vs_progr_9e053504" VARCHAR -- Pulse Amplitude QLRs. RMS Voltage Magnitude (mV) Vs Programmed Peak-to-peak Amplitude (AWG V (p-p)) For 50 KHz, 150 KHz, 5.5 MHz, 15.05 MHz, 30.05 MHz, And 50.05 MHz Waveforms. The Rms Voltage Values For The 30.05 MHz Tone Shown Here And In The Figure Are +5.5 MV Higher Than The Measured Values. This Addition Was Included For Visual Clarity.,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2
);CREATE TABLE fig7_bottom_slope_phase (
"the_phase_of_the_complex_slope_of_the_measured_feedthr_de9bc720" VARCHAR -- The Phase Of The Complex Slope Of The Measured Feedthrough Error, Relative To The Output Waveform Phase At 0.43 AWG, As A Function Of Pulse Amplitude (over 0.4-0.5 AWG V (p-p)) As A Function Of Output Waveform Frequency (MHz). The Complex Slope Calculated From The Change In The Measured Output Voltage While The System Is Quantum-locked (qlr Slopes Phase, Radians Normalized To JJ Voltage) Agrees With That Of The 10 DB-adjusted Feedthrough Error Measured Directly By Significantly Attenuating The Pulses (feed Slopes Phase, Radians Normalized To JJ Voltage) To Remove The JJ Voltage Contribution. Standard Uncertainties Of The Slope Phases Based On The Linear Regression Are Included In Radians.,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2,
"unnamed_3" VARCHAR -- Unnamed: 3,
"unnamed_4" VARCHAR -- Unnamed: 4,
"unnamed_5" VARCHAR -- Unnamed: 5
);CREATE TABLE fig7_top_slope_mag (
"the_magnitude_of_the_complex_slope_of_the_measured_fee_f32f3143" VARCHAR -- The Magnitude Of The Complex Slope Of The Measured Feedthrough Error As A Function Of Pulse Amplitude (over 0.4-0.5 AWG V (p-p)) As A Function Of Output Waveform Frequency (MHz). The Complex Slope Calculated From The Change In The Measured Output Voltage While The System Is Quantum-locked (qlr Slopes Mag, (mV / AWG V (p-p))) Agrees With That Of The 10 DB-adjusted Feedthrough Error Measured Directly By Significantly Attenuating The Pulses (feed Slopes Mag, (mV / AWG V (p-p))) To Remove The JJ Voltage Contribution. Standard Uncertainties Of The Slope Magnitudes Based On The Linear Regression Are Included In MV / AWG V (p-p).,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2,
"unnamed_3" VARCHAR -- Unnamed: 3,
"unnamed_4" VARCHAR -- Unnamed: 4,
"unnamed_5" VARCHAR -- Unnamed: 5
);CREATE TABLE fig8_bottom_x_intercept (
"the_x_intercepts_of_the_fits_in_fig8_top_are_plotted_i_db1ea539" VARCHAR -- The X-intercepts Of The Fits In Fig8 Top Are Plotted In AWG V (p-p). We Observe A Non-zero X-intercept Above ~6 MHz. Standard Uncertainties Of The X-intercepts Based On The Linear Regression Are Included In AWG V (p-p).,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2
);CREATE TABLE fig8_top_direct_feed (
"rms_voltage_magnitude_mv_measured_by_the_dut_digitizer_31229e73" VARCHAR -- RMS Voltage Magnitude (mV) Measured By The DUT Digitizer At The Pattern Frequency Which Is Entirely Due To The Feedthough Error (at Several Frequencies Up To 50 MHz). This Voltage Is Plotted Versus Programmed Peak-to-peak Pulse Amplitude (AWG V (p-p)). Data Is Taken After Inserting 10 DB Of Additional Attenuation So That The JJs Do Not Contribute To The Voltage Waveform. The Voltages Shown Here, And In The Figure, Are Scaled Up By +10 DB From The Measured Voltages (they Are 10 DB Larger) To Show The Feedthrough Error During Normal Operation. We Perform Linear Regressions Of These Voltages (fit Direct Feed MV, Fit Direct Feed Pulse Amp) Over The Previously Identified Global Pulse Amplitude Quantum Locking Range (0.4-0.5 AWG V (p-p)).,
"unnamed_1" VARCHAR -- Unnamed: 1,
"unnamed_2" VARCHAR -- Unnamed: 2,
"unnamed_3" VARCHAR -- Unnamed: 3,
"unnamed_4" VARCHAR -- Unnamed: 4
);Anyone who has the link will be able to view this.