Related papers: An open-source high-frequency lock-in amplifier
A low-noise amplifier (LNA) amplifies a very low-power signal without significantly degrading its signal-to-noise ratio. This paper provides the design of a linear low noise amplifier with the transistor BFP 640 using bilateral approach…
We demonstrate theoretically that robust mode-locking can be achieved on a semiconductor chip with a waveguide array architecture. The waveguide arrays are used as an ideal saturable absorption mechanism for initial noise start-up as well…
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…
This paper describes an automatic switching of modulation method to reconfigure transceivers of Software Defined Radio (SDR) based wireless communication system. The programmable architecture of Software Radio promotes a flexible…
We demonstrate a ventilated metamaterial absorber operating at low frequency (< 500 Hz).With only two layers of the absorption units, high-efficiency absorption (> 90%) has been achieved in both simulations and experiments. This…
Portable mid-infrared (mid-IR) spectroscopy and sensing applications require widely tunable, narrow linewidth, chip-scale, single-mode sources without sacrificing significant output power. However, no such lasers have been demonstrated…
This letter presents principles and applications of a virtual multi-channel lock-in amplifier that is a simple but effective method to recover small ac signal from noise with high presison. The fundamentals of this method are based on…
We present a detailed analysis of an application of frequency modulation (FM) spectroscopy in the high modulation depth limit. We have recently completed and reported a measurement of the Stark shift in the indium $5p_{1/2}\rightarrow…
We demonstrate a hybrid analog+digital electronic lock to stabilize a dynamically tunable rf offset between two lasers. Our method features an 80 MHz capture range, +/- 7 GHz tuning range, frequency agility of 1 MHz/microsecond, and low…
This paper demonstrates designing and developing of an Ultra-Low Noise Amplifier which should potentially increase the sensitivity of the existing Magnetic Resonance Imaging (MRI) systems. The Design of the LNA is fabricated and…
A transimpedance amplifier has been designed for scanning tunneling microscopy (STM). The amplifier features low noise (limited by the Johnson noise of the 1 G{\Omega} feedback resistor at low input current and low frequencies), sufficient…
Emerging health-monitor applications, such as information transmission through multi-channel neural implants, image and video communication from inside the body etc., calls for ultra-low active power (<50${\mu}$W) high data-rate,…
We present a novel laser mode-locking scheme and discuss its unusual properties and feasibility using a theoretical model. A large set of single-frequency continuous-wave lasers oscillate by amplification in spatially separated gain media.…
The lack of high power integrated lasers have been limiting silicon photonics. Despite much progress made in chip-scale laser integration, power remains below the level required for key applications. The main inhibiting factor for high…
A 20 GHz LLRF system is being built using a two-board(RF Front End + ADC/DAC/FPGA) architecture. The RF Front End provides 8 down-converting channels and 3 up-converting channels (5.5-20 GHz RF to 0.05-3 GHz IF). Separate, phase locked,…
This paper reports the design and experimental characterization of a cryogenic compact low-power 60GHz amplifier for control of electron/hole spin qubits, as elementary building block for monolithic Si quantum processors. Tested at 2 K, the…
We present a compact laser frequency stabilization method by locking a 556 nm laser to a high-precision wavelength meter. Unlike traditional schemes that rely on optical cavities or atomic references, we stabilize the laser frequency via a…
Small- and large-signal RF characteristics were measured on AlN GaN HEMTs with 80-160 nm gate length and 100-300 {\mu}m width. Consistent with the literature, current-gain cut-off frequency and maximum frequency of oscillation were found to…
We developed a scanning DC SQUID microscope with novel readout electronics capable of wideband sensing RF magnetic fields from 50 to 200 MHz and simultaneously providing closed-loop response at kHz frequencies. To overcome the 20 MHz…
The amplitude of self-oscillating mechanical resonators in cavity optomechanical systems is typically limited by nonlinearities arising from the cavity's finite optical bandwidth. We propose and demonstrate a feedback technique for…