Amplitude Mode in the Quantum Phase Model

Two-mode quantum phase

Phase-amplitude coupling characteristics in directly modulated quantum dot lasers

Dynamic amplitude-phase coupling in quantum-dot lasers

The well-known a-factor is a convenient measure to describe the magnitude of the amplitude-phase coupling of semiconductor lasers. But is the a-factor really a parameter? First-principle simulations of InGaAs quantum-dot lasers and amplifiers show that in spatially extended quantum-dot laser structures, the amplitude phase coupling is far from being a constant. Our computation of the a-factor d...

Quantum model for electro-optical amplitude modulation.

We present a quantum model for electro-optic amplitude modulation, which is built upon quantum models of the main photonic components that constitute the modulator, that is, the guided-wave beamsplitter and the electro-optic phase modulator and accounts for all the different available modulator structures. General models are developed both for single and dual drive configurations and specific r...

Quantum phase transition in the quantum compass model

In this work, we show that the quantum compass model on a square lattice can be mapped to a fermionic model with local-density interaction. We introduce a mean-field approximation where the most important fluctuations, those perpendicular to the ordering direction, are taken into account exactly. It is found that the quantum phase transition point at Jx=Jz marks a first-order phase transition. ...