Thermal-noise-limited higher-order mode locking of a reference cavity

Compact, thermal-noise-limited reference cavity for ultra-low-noise microwave generation.

We demonstrate an easy-to-manufacture 25-mm-long ultra-stable optical reference cavity for transportable photonic microwave generation systems. Employing a rigid holding geometry that is first-order insensitive to the squeezing force and a cavity geometry that improves the thermal noise limit at room temperature, we observe a laser phase noise that is nearly thermal noise limited for three freq...

Toward higher-order passive harmonic mode-locking of a soliton fiber laser.

We report >13 MHz/mW pump power efficiency in increasing the repetition rate of passive harmonic mode-locking by engineering the soliton pulse energy in Er fiber lasers incorporating carbon nanotube saturable absorber. Stable pulses with a ∼5 GHz repetition rate and 40 dB of super-mode suppression are demonstrated with only ∼400 mW pump power in a single-clad fiber laser.

Higher Order Dynamic Mode Decomposition

Phase Noise Compensation with Limited Reference Symbols

Phase noise (PN) can cause severe link performance degradation in orthogonal frequency division multiplexing (OFDM) systems. In this work, we propose an efficient PN mitigation algorithm where the PN statistics are used to obtain more accurate channel estimates. As opposed to prior PN mitigation schemes that assume perfect channel information and/or require abundant reference symbols, the propo...

Statistical-mechanics theory of active mode locking with noise.

Actively mode-locked lasers with noise are studied employing statistical mechanics. A mapping of the system to the spherical model (related to the Ising model) of ferromagnets in one dimension that has an exact solution is established. It gives basic features, such as analytical expressions for the correlation function between modes, and the widths and shapes of the pulses [different from the K...