相关论文: Noise Performance of Lumped Element Direct Current…
Dephasing induced by residual thermal photons in the readout resonator is a leading factor limiting the coherence times of qubits in the circuit QED architecture. This residual thermal population, of the order of $10^{-1}$--$10^{-3}$, is…
This paper demonstrates designing and developing of an Ultra-Low Noise Amplifier which should potentially increase the sensitivity of the existing Magnetic Resonance Imaging (MRI) systems. The Design of the LNA is fabricated and…
We perform a detailed analysis of how an amplified interferometer can be used to enhance the quality of a dispersive qubit measurement, such as one performed on a superconducting transmon qubit, using homodyne detection on an amplified…
Using a simple lumped-circuit model, we numerically study the dependence of the voltage gain and noise on the amplifier's parameters. Linear, quasi-linear, and nonlinear regimes are studied. We have shown that the voltage gain of the…
Kinetic inductance traveling-wave parametric amplifiers (KI-TWPA) have a wide instantaneous bandwidth with near quantum-limited performance and a relatively high dynamic range. Because of this, they are suitable readout devices for…
Low-noise cryogenic microwave amplifiers are widely used in applications such as radio astronomy and quantum computing. On-wafer noise characterization of cryogenic low-noise transistors is desirable because it facilitates more rapid…
Low-noise amplifiers are of great importance in the field of quantum technologies. We study a thermally driven parametric amplifier based on a superconductor-insulator-graphene-insulator-superconductor (SIGIS) junction coupled to a…
Most microwave readout architectures in quantum computing or sensing rely on a semiconductor amplifier at 4 K, typically a high-electron mobility transistor (HEMT). Despite its remarkable noise performance, a conventional HEMT dissipates…
We present improved performance for a 92 to 96 GHz cross-spectrum phase modulated (PM) noise measurement system reported. The system is principally designed to measure amplifiers in pulsed mode as well as in CW mode at a given pulse…
The separation and optimization of noise components is critical to microwave-kinetic inductance detector (MKID) development. We analyze the effect of several changes to the lumped-element inductor and interdigitated capacitor geometry on…
Quantum mechanics can strongly influence the noise properties of mesoscopic devices. To probe this effect we have measured the current fluctuations at high-frequency (5-90 GHz) using a superconductor-insulator-superconductor tunnel junction…
We present the design and characterisation of a low-noise, resonant input transimpedance amplified photodetector. The device operates at a resonance frequency of $90 \,\textrm{MHz}$ and exhibits an input referred current noise of…
We measure the effect of externally applied broadband Nyquist noise on the intrinsic Nyquist dephasing rate of electrons in a two-dimensional electron gas at low temperatures. Within the measurement error, the phase coherence time is…
Microwave Kinetic Inductance Detectors (MKIDs) have been demonstrated as capable phonon sensors when coupled to crystalline substrates, and have been proposed as detectors for next-generation rare-event searches such as for the direct…
We demonstrate an amplitude-to-phase (AM-PM) conversion coefficient for a balanced optical-microwave phase detector (BOM-PD) of 0.001 rad, corresponding to AM-PM induced phase noise 60 dB below the single-sideband relative intensity noise…
The quantum bits (qubits) on which superconducting quantum computers are based have energy scales corresponding to photons with GHz frequencies. The energy of photons in the gigahertz domain is too low to allow transmission through the…
Any quantum device that amplifies coherent states of a field while preserving their phase generates noise. A nonlinear, phase-invariant amplifier may generate less noise, over a range of input field strengths, than any linear amplifier with…
We demonstrate a high-Q ($>5 \times 10^{6}$) swept-frequency membrane mechanical resonator achieving octave resonance tuning via an integrated heater and an unprecedented acceleration noise floor below 1 $\mu$g Hz$^{-1/2}$ for frequencies…
In this study, we present the design and analysis of a Low Noise Amplifier tailored specifically for quantum applications. We selected the HEMT for its unique noise reduction properties, crucial for quantum engineering. The main goal is to…
We present measurements of the low-frequency noise of microstrip-coupled, lumped-element aluminum kinetic inductance detectors that use hydrogenated amorphous silicon parallel-plate capacitors (Al/a-Si:H MS-PPC-LEKIDs), which are under…