The frequency noise properties of commercial distributed feedback quantum cascade lasers emitting in the 4.6 μm range and operated in cw mode near room temperature (277 K) are presented. The measured frequency noise power spectral density reveals a flicker noise dropping down to the very low level of <100 Hz(2)/Hz at 10 MHz Fourier frequency and is globally a factor of 100 lower than data recen...

Davydov’s model of solitons in α-helix protein chains is shown to display features of self-organized criticality (SOC), i.e., power law behaviour of correlations in space and 1/f noise, as a consequence of considering random peptide group displacements from their (periodic) equilibrium positions along a chain. This may shed light on a basic mechanism leading to obtain flicker noise in α-helix p...

This article analyzes the design of a low-noise amplifier intended as the input front-end for the measurement of the low-frequency components (below 10 Hz) of a 50 Ω source. Low residual flicker is the main desired performance. This feature can only be appreciated if white noise is sufficiently low, and if an appropriate design ensures dc stability. An optimal solution is proposed, in which the...

ANALYSIS AND DESIGN OF LOW-JITTER OSCILLATORS Justin Jennings Fitzpatrick Department of Electrical and Computer Engineering Master of Science This thesis presents an examination of the jitter performance of different oscillator types in the presence of flicker noise, white noise and power supply noise. Key results are achieved using time domain simulations to determine cycle jitter of several d...

A previously developed numerical model based on Maxwell–Bloch equations was modified to simulate optical coherent transient and spectral hole burning processes with noisy laser sources. Random walk phase noise was simulated using laser-phase sequences generated numerically according to the normal distribution of the phase shift. The noise model was tested by comparing the simulated spectral hol...

The triode was invented by Lee de Forest in 1907, and soon afterwards the first amplifiers were built. By 1921 the "thermionic tube" amplifiers were so developed that C. A. Hartmann [1] made the first courageous experiment to verify Schottky's formula for the shot noise spectral density [2]. Hartmann's attempt failed, and it was finally J. B. Johnson who successfully measured the predicted whit...

The authors report a detailed investigation of the flicker noise (1/f noise) in graphene films obtained from chemical vapour deposition (CVD) and chemical reduction of graphene oxide. The authors find that in the case of polycrystalline graphene films grown by CVD, the grain boundaries and other structural defects are the dominant source of noise by acting as charged trap centres resulting in h...

This paper describes sub-harmonic mixer designed in 0.18 μm CMOS process and intended for use in low-power IEEE 802.15.4-compliant 2.4 GHz transceiver. Device addresses the following issues of the direct conversion architecture: flicker-noise, LO leakage and oscillator pulling.

Four algorithms for simulating flicker FM phase noise (f−3 spectrum) are given, two old and two new. Their Allan deviation and mean square time interval error (MSTIE) are examined. The MSTIE shows that one of the old algorithms has deficient long-term phase deviations on average. The Allan deviation does not reveal this deficiency.