Fiber-based parametric devices

Parametric devices based on four-wave mixing (FWM) in fibers can amplify, frequency convert, phase conjugate, delay, regenerate and sample optical signals in communication systems. FWM is driven by pump-induced nonlinearity and suppressed by dispersion-and nonlinearity-induced wavenumber mismatch. In this tutorial, I will review the basic physics of FWM, including polarization-dependent coupling, wavenumber matching, energy, momentum and angular momentum conservation, and signal-phase-(in) sensitive operation. I will also review the quantum noise properties of parametric devices and communication links based upon them. Applications to be discussed include tunable radiation generation by optical parametric oscillators, stroboscopic and real-time sampling of high-bit-rate signals, impairment reduction by phase conjugation and phase-sensitive amplification, and buffering by frequency conversion and dispersion. If time permits, photon generation and frequency conversion in quantum information experiments will be discussed briefly.