US 2008/0174856 A1 · SEMICONDUCTOR OPTICAL AMPLIFIER DEVICE AMPLIFYING EXTERNAL LIGHT SIGNAL AND DRIVING APPARATUS THEREFOR

Abstract

An active layer has a quantum well structure formed of InGaAsP, and includes a saturable absorption region and optical amplification regions. To the saturable absorption region, a voltage is applied through a p-electrode, independent from the optical amplification region. To the optical amplification regions, currents are injected through p-electrodes, respectively. An input light Pin entering through a plane of incidence is generated by adding optical noise of white noise, to a light signal assuming binary optical intensity of “1” or “0”. The saturable absorption region and optical amplification regions are formed satisfying conditions that a waveform converting element provides a semiconductor laser of bistable state.

Claims29

Dependent claims

A semiconductor optical amplifier device having discontinuous input-output characteristic for input light and output light, comprising:

an active layer including an optical amplification region and a saturable absorption region;
an electrode of a first polarity injecting a current and/or applying voltage to said active layer;
and
an electrode of a second polarity provided corresponding to said electrode of first polarity;
wherein
a first bias voltage is applied to said saturable absorption region such that a rising threshold value of said input-output characteristic lowers at a timing when the input light assumes “1” and a second bias voltage is applied to said saturable absorption region such that a falling threshold value of said input-output characteristic rises at a timing when the input light assumes “0”, through said electrodes of first and second polarities.

3 more elements

An apparatus for driving a semiconductor optical amplifier device having discontinuous input-output characteristic for input light and output light, comprising:

a semiconductor optical amplification module including said semiconductor optical amplifier device and a photo-electric converting element detecting said output light and outputting a reception signal;
and
a feedback control circuit receiving said reception signal and outputting a control signal for adjusting input-output characteristic of said semiconductor optical amplifier device;
wherein said semiconductor optical amplifier device includes
an active layer including an optical amplification region and a saturable absorption region,
an electrode of a first polarity injecting a current and/or applying voltage to said active layer, and
an electrode of a second polarity provided corresponding to said electrode of first polarity;
and
a first bias voltage is applied to said saturable absorption region such that a rising threshold value of said input-output characteristic lowers at a timing when the input light assumes “1” and a second bias voltage is applied to said saturable absorption region such that a falling threshold value of said input-output characteristic rises at a timing when the input light assumes “0”, through said electrodes of first and second polarities.

6 more elements

Dependencies are inferred from the claim text.

Semiconductor optical amplifier device amplifying external light signal and driving apparatus therefor

Life of this patent

Semiconductor optical amplifier device amplifying external light signal and driving apparatus therefor

Life of this patent

Abstract

Claims29