Symmetric highly efficient (/spl sim/0 dB) wavelength conversion based on four-wave mixing in quantum dot optical amplifiers

Akiyama, T.; Kuwatsuka, H.; Hatori, Nobuaki; Nakata, Yoshihiro; Ebe, H.; Sugawara, Mitsuru

doi:10.1109/lpt.2002.1021995

Cited by 122 publications

(51 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When a linear amplification of the input signal is required, the flat section of the gain characteristics should extend towards as high input power as possible, leading to a distortion-free amplification of arbitrarily strong optical signals [LAE06a]. On the other hand, optical signals with powers in the nonlinear regime induce a nonlinear response of the amplifier, which can be used, e.g., for wavelength conversion via four-wave-mixing [AKI02,QAS04,MAJ11a,SCH12e] or cross-gain-modulation [KIM09a,MEU10].…”

Section: Gain Saturationmentioning

confidence: 99%

“…Here, a linear amplification with a low noise figure is required, to ensure low distortion of the input signal [AKI03,BER04,USK05]. On the other hand, nonlinear optical applications, such as four-wave-mixing [AKI02,QAS04,MAJ11a,SCH12e] and cross-gain modulation [KIM09a,MEU10,CON10] for wavelength conversion, as well as regenerative amplification, require a nonlinear response of the optical amplifier. In the nonlinear amplification regime the amplifier response is input-power dependent and will thus lead to signal distortions, which can be utilized, e.g., for pulse shaping…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nonlinear and Nonequilibrium Dynamics of Quantum-Dot Optoelectronic Devices

Lingnau

2015

Springer Theses

View full text Add to dashboard Cite

In this thesis the dynamics and performance of optoelectronic devices based on semiconductor quantum-dots are investigated.In the first part, the dynamics of quantum-dot lasers under external perturbations is discussed. Using a microscopically based balance equation model that incorporates detailed charge-carrier scattering dynamics and the possibility to describe nonequilibrium between intra-band electronic states, the relaxation oscillations of the quantum-dot laser are investigated. Three qualitatively different dynamic regimes are identified in dependence of the scattering rates -the "constantreservoir" regime for slow scattering, the "overdamped" regime, and the "synchronized" regime for high scattering -characterized by a varying degree of nonequilibrium between the quantum-dot and reservoir states.Important differences to conventional lasers are found in the modulation response and the dynamics in optical injection and feedback setups. Common theoretical models and approaches used to describe these applications are shown to yield inaccurate predictions, especially in the "constant-reservoir" and "overdamped" dynamic regimes. An important consequence is that the amplitude-phase coupling in quantum-dot lasers, commonly described by the α-factor, differs from conventional descriptions due to the desynchronization of gain and refractive index. While the α-factor describes bifurcations of fixed points accurately, it fails in describing dynamic solutions and overestimates the extent of complex dynamics. The observed low sensitivity to optical perturbations in quantum-dot lasers can therefore be attributed partly to the charge-carrier nonequilibrium. Three quantum-dot laser models on different levels of sophistication are presented that can accurately describe the quantum-dot nonequilibrium dynamics.In the second part of the thesis, the performance of quantum-dot semiconductor optical amplifiers is investigated, and two types of applications unique to quantum-dots as active medium are discussed. The ground and excited states of the quantum-dots allow an ultra-broad-band amplification of optical data streams. Amplified signals on the ground-state frequencies are shown to generally exhibit higher quality than on the excited state, due to a lower sensitivity of the groundstate to carrier-density variations. Nevertheless the quantum-dot amplifier is found to allow effective amplification on both frequency ranges. Furthermore, a parameter range is identified that allows for a simultaneous amplification of data signals on the ground and excited state in a counter-propagating setup.The long microscopically polarization dephasing times in quantum-dots are found to enable quantum-coherent interactions on a macroscopic scale at room-temperature. By comparison with experiments, the occurrence of Rabi-oscillations by amplification of ultra-short pulses is demonstrated. Quantum-dot based devices could therefore be used for future applications based on quantum-coherent effects.

show abstract

Section: Gain Saturationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Nonlinear and Nonequilibrium Dynamics of Quantum-Dot Optoelectronic Devices

Lingnau

2015

Springer Theses

View full text Add to dashboard Cite

show abstract

“…First the bound conduction band states of the QD, which we assume known at this point, are fitted with a parabolic band (similar to a bulk DOS) with the curvature determined by the effective electron mass. Two equations determining the effective conduction bandedge , and the effective single dot volume, , are obtained by integrating over the bulk-like DOS from to the bound energy of either the GS or ES, multiplying by the effective volume of a single dot , and equating it with either the number of states including spin of the GS , or that of the combined GS and ES (19) From these we find (21) and (22) If we now assume , where is the relative bandgap difference between the two materials, originating from the conduction band, we can determine the effective valence bandedge . The contribution to the total effective DOS of the valence band from all dots in the device , can now be written as (23) with being the Heaviside step function and the total number of dots in each dot population.…”

Section: A Hole Occupation Probabilitiesmentioning

confidence: 99%

“…Recently, also QD SOAs have received some attention, mainly focused on their nonlinear properties. Main results include the demonstration of ultrafast gain recovery [17], signal processing and pattern free amplification up to 40 Gbit/s [18] and unique four-wave mixing properties [19]. With respect to their application as linear amplifiers, QD SOAs were predicted to exhibit low noise figure and high saturation power [20], [21].…”

Section: Introductionmentioning

confidence: 99%

Saturation and noise properties of quantum-dot optical amplifiers

Berg

Mørk

2004

IEEE J. Quantum Electron.

143

View full text Add to dashboard Cite

Abstract-Based on extensive numerical calculations, quantum-dot (QD) amplifiers are predicted to offer higher output power and lower noise figure compared to bulk as well as quantum well amplifiers. The underlying physical mechanisms are analyzed in detail, leading to the identification of a few key requirements that QD amplifiers should meet in order to achieve such superior linear characteristics. The existence of a highly inverted wetting layer or barrier region, acting as a carrier reservoir, is central to this performance enhancement. It is shown that amplified spontaneous emission acts to decrease the inversion of the wetting layer states, thus helping to quench the gain of these states, which might otherwise dominate.

show abstract

“…46-49. Wavelength switching experiments employing ultrashort pulses were published in refs. [50][51][52]. In this paper, we investigate nonlinear carrier dynamics in a MQW-SOA in the context of ultrafast all-optical logic.…”

Section: Introductionmentioning

confidence: 99%

All-Optical Switching and Wavelength Conversion Based on Ultrafast Nonlinearities in Semiconductor Optical Amplifiers

Dorren

Mishra

Yang

et al. 2004

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We investigate all-optical switching and wavelength conversion based on ultrafast nonlinearities in a multi-quantum-well semiconductor optical amplifier. We present a rate equation model that accounts for two-photon absorption, free-carrier absorption, self-and cross phase modulation, carrier heating, spectral, spatial hole burning and self-and cross polarization modulation. We demonstrate optical AND gate operation using a semiconductor optical amplifier placed in an asymmetric March-Zehnder interferometer and we show that the gate can be operated using 800 fJ optical pulses with duration of 200 fs. We also investigate wavelength conversion based on ultrafast nonlinear polarization rotation. We found a conversion efficiency of 12 dB for control pulse energies of 10 pJ.

show abstract

Symmetric highly efficient (/spl sim/0 dB) wavelength conversion based on four-wave mixing in quantum dot optical amplifiers

Cited by 122 publications

References 6 publications

Nonlinear and Nonequilibrium Dynamics of Quantum-Dot Optoelectronic Devices

Nonlinear and Nonequilibrium Dynamics of Quantum-Dot Optoelectronic Devices

Saturation and noise properties of quantum-dot optical amplifiers

All-Optical Switching and Wavelength Conversion Based on Ultrafast Nonlinearities in Semiconductor Optical Amplifiers

Contact Info

Product

Resources

About