Nonlinear processes responsible for nondegenerate four-wave mixing in quantum-dot optical amplifiers

Abstract

Wavelength conversion using nondegenerate four-wave mixing in quantum-dot optical amplifiers is investigated. From the detuning frequency dependence of χ(3), derived from the conversion efficiency, we consider that, within the range of detuning in the experiment, spectral-hole burning and carrier heating are responsible, and that their time constants, i.e., carrier relaxation time to the ground state and the phonon scattering time, are in the range of 60–140 and 200–400 fs, respectively. This indicates that the carrier supply to the ground level via relaxation from the higher levels is very fast and that a broad conversion bandwidth comparable to that of quantum-well devices is ensured.

High Speed All-Optical Logic Gate Using QD-SOA and its Application

“…The commonly used QD-SOA is InAs/GaAs QD-SOA, with InAs Stranski-Krastanov (SK) quantum dots embedded in GaAs layer [21,22]. This type of device can provide ~15dB gain at wavelength 1550nm with noise figure as low as 7 dB [12].…”

“…Thus, as m increases the randomness of PRBS sequence becomes better. Two other kinds of more secure key-stream generators, cascaded design and parallel design were also presented, shown in Figure 21 and Figure 22 [22]. The cascaded design consists of three cascaded linear feedback shift registers (LFSR) which can generate all-optical PRBS.…”

Nanophotonic Devices Based on Semiconductor Quantum Nanostructures

“…Copyright c 2016 The Institute of Electronics, Information and Communication Engineers Numerous approaches to prepare high-density QDs have been reported, many of which involve new Sb-or N-containing materials [10]- [15]. Some QDs containing Sb exhibit densities as high as 1 × 10 11 cm −2 ; however, these materials exhibit poor crystal quality.…”

Four-Wave-Mixing-Based Dual-Wavelength Conversion in a Semiconductor Optical Amplifier

“…Converters based on cross-gain and cross-phase modulation (XGM, XPM) in semiconductor optical amplifiers (SOAs) can be operated at very high speeds [6] and have great integration potential but offer a simple conversion mechanism only for a single amplitude modulated signal, although inclusion of SOAs in more elaborate setups has yielded a more generalized convertor, suitable for either phase or amplitude modulated signal, yet still incapable of simultaneous conversion [7]. The use of SOAs with FWM has several demonstrations [8], [9]; in many of them, a strong optical data-carrier is converted to one or many (multicast) output carriers, achieving high efficiency FWM but with a single data pattern being copied each time. Multiple conversions using a single strong continuouswave (CW) pump and multiple modulated carriers was suggested but only demonstrated for a single modulation format, at low bit rates and with considerable penalty [10].…”