Monolithic photonic integrated circuit (PIC) with a plurality of integrated arrays of laser sources and modulators employing an extended identical active layer (EIAL)

Patent metadata

Field	Value
Publication number	US-10012797-B1
Application number	US-4546205-A
Country	US
Kind code	B1
Filing date	Jan 27, 2005
Priority date	Oct 8, 2002
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

A semiconductor monolithic transmitter photonic integrated circuit (TxPIC) comprises two different situations, either at least one signal channel in the PIC having a modulated source with the channel also extended to include at least one additional element or a plurality of modulated sources comprising N signal channels in the PIC of different transmission wavelengths, where N is equal to or greater than two (2), which may also approximate emission wavelengths along a standardized wavelength grid. In these two different situations, a common active region for such modulated sources and additional channel elements is identified as an extended identical active layer (EIAL), as it extends from a single modulated source to such additional channel elements in the same channel and/or extends to additional modulated sources in separate channels where the number of such channels is N equal to two or greater. The emission wavelength of laser sources in the modulated sources have different positively detuned offsets of the laser emission wavelength relative to the laser active region wavelength, i.e., (λ L,i −λ PL,L,j >0), and their emission wavelengths form a wavelength grid which may substantially conform to a standardized wavelength grid, such as the ITU grid. These laser sources in the modulated sources with an EIAL are preferentially detuned in the range, for example, of about 20 nm to about 70 nm, preferentially from about 25 nm to about 50 nm, from the active region wavelength of the modulated sources.

First claim

What is claimed is:

1. A photonic integrated circuit comprising:
a substrate;
a first modulated source provided on the substrate, the first modulated source including a first laser source and a first modulator that modulates light output from the first laser source;
a second modulated source provided on the substrate, the second modulated source including a second laser source and a second modulator that modulates light output from the second laser source; and
an extended identical active layer that forms a common active region for the first and second modulated sources, each of the first and second modulated sources having a corresponding one of a plurality of detuned offset values.

2. The photonic integrated circuit of claim 1 , further comprising a plurality of modulated sources provided on the substrate, such that the first and second modulated sources are corresponding first and second of the plurality of modulated sources provided on the substrate.

3. The photonic integrated circuit of claim 1 wherein the common active region contains a layer which is an aluminum-containing Group III-V compound.

4. The photonic integrated circuit of claim 3 wherein the aluminum-containing Group III-V compound contains AlInGaAs, AlInGaAsP, AlInAsN, or AlInGaAsN.

5. The photonic integrated circuit of claim 1 wherein the extended identical active layer contains AlInGaAs, InGaAsP, AlInGaAsP, InGaP, InGaAs, InAsP, or InGaAsNSb, or combinations thereof.

6. The photonic integrated circuit of claim 1 , wherein the first modulated source comprises a first laser having a first of the plurality of detuned offset values and the second modulated source comprises a second laser having a second of the plurality of detuned offset values, the first detuned offset value being different than the second detuned offset value.

7. The photonic integrated circuit of claim 6 wherein each of the first and second detuned offset values are positively detuned offset values.

8. The photonic integrated circuit of claim 1 wherein the extended identical active layer is a first extended identical active layer, the photonic integrated circuit further comprising a second extended identical active layer.

9. The photonic integrated circuit of claim 1 wherein the first modulated source is tunable.

10. The photonic integrated circuit of claim 1 further comprising a heater for tuning a wavelength of the first modulated source.

11. The photonic integrated circuit of claim 1 , where trim selective area growth is employed in the fabrication of the photonic integrated circuit to expand an operation window of the first and second modulated sources.

12. The photonic integrated circuit of claim 11 , wherein the first modulator source comprises a first laser source and a first electroabsorption modulator.

13. The photonic integrated circuit of claim 12 wherein trim selective area growth is employed in the fabrication of the first electroabsorption modulator to reduce a range of laser-modulator detuning.

14. The photonic integrated circuit of claim 12 wherein trim selective area growth is employed in the fabrication of the first laser source.

15. The photonic integrated circuit of claim 1 wherein an active region wavelength in one of the first and second modulated sources is varied through the use of trim selective area growth where an amount of variation is approximately in the range of about 1 nm to about 20 nm.

16. The photonic integrated circuit of claim 1 , further comprising an optical combiner coupled to receive a first output from the first modulated source and a second output from the second modulated source.

17. The photonic integrated circuit of claim 1 , further comprising a first optical element coupled to the first modulated source and a second optical element coupled to the second modulated source, the first and second optical element being a power changing element or a multifunctional element, or both.

18. The photonic integrated circuit of claim 1 , wherein the first and second modulated sources are first and second of a plurality of modulated sources, each of the plurality of modulated sources comprising a corresponding one of a plurality of laser sources, the plurality of laser sources having a laser spectrum span in the range 0≤(N−1)Δλ≤30 nm.

19. The photonic integrated circuit of claim 1 , wherein the first and second modulated sources are first and second of a plurality of modulated sources, each of the plurality of modulates sources comprising a corresponding one of a plurality of laser sources, the plurality of laser sources having a laser spectrum span in the range 0≤(N−1)Δλ≤15 nm.

20. The photonic integrated circuit of claim 1 , wherein the first and second modulated sources are constrained in laser-modulator detuning in a range of about 20 nm to about 70 nm.

21. The photonic integrated circuit of claim 1 , wherein the first and second modulated sources are constrained in laser-modulator detuning in a range of about 25 nm to about 50 nm.

22. The photonic integrated circuit of claim 1 , wherein the first laser source includes a first grating providing a respective one of a plurality of emission wavelengths and the second laser source includes a second grating providing a respective one of the plurality of emission wavelengths, each of the first and second gratings comprising a complex-couple grating, a phase shift formed in the grating, or both.

23. The photonic integrated circuit of claim 1 , wherein the first laser source is a first continuous wave laser and the first modulator is a first electro-optic modulator and the second laser source is a second continuous wave laser and the second modulator is a second electro-optic modulator, the first continuous wave laser having a first of the plurality of detuned offset values relative the photoluminescence or exciton peak of the extended identical active layer and the second continuous wave laser having a second of the plurality of detuned offset values relative the photoluminescence or exciton peak of the extended identical active layer, the first of the plurality of detuned offset values being different from the second of the plurality of detuned offset values.

24. The photonic integrated circuit of claim 23 , wherein the first continuous wave laser has a first of a plurality of wavelengths and the second continuous wave laser has a second of the plurality of wavelengths, the first and second of the plurality of wavelengths being red-shifted relative to the first and second modulator extended identical active layer.

25. The photonic integrated circuit of claim 23 , wherein the first and second of the plurality of wavelengths are detuned to be close to the absorption edge of the first and second modulator extended identical active layer.

26. A photonic integrated circuit comprising:
a substrate;
a modulated source provided on the substrate, the modulated source comprising a laser source element and a modulator element that form a signal channel;
an integrated element provided on the substrate and coupled to the modulated source, such that the integrated element is included in the signal channel; and
an extended identical active layer that forms a common active region for the laser source element, modulator element and the integrated element in the signal channel, and
a laser emission wavelength of the laser source element is wavelength red-shifted relative to a photoluminescence o

Assignees

• Nagarajan Radhakrishnan L
• Kish Jr Fred A
• Kato Masaki
• Joyner Charles H
• Welch David F
• Salvatore Randal A
• Schneider Richard P
• Ziari Mehrdad
• Lambert Damien Jean Henri
• Hurtt Sheila K
• Dentai Andrew G
• Mathur Atul
• Dominic Vincent G
• Infinera Corp

Inventors

• Nagarajan Radhakrishnan L
• Kish Jr Fred A
• Kato Masaki
• Joyner Charles H
• Welch David F
• Salvatore Randal A
• Schneider Richard P
• Ziari Mehrdad
• Lambert Damien Jean Henri
• Hurtt Sheila K
• Dentai Andrew G
• Mathur Atul
• Dominic Vincent G

Classifications

• G02B6/29395 Primary

  configurable, e.g. tunable or reconfigurable (switching G02B6/35) · CPC title

• H01S5/1221

  Detuning between Bragg wavelength and gain maximum · CPC title

• H01S5/02325

  Mechanically integrated components on mount members or optical micro-benches · CPC title

• H01S5/0268

  Integrated waveguide grating router, e.g. emission of a multi-wavelength laser array is combined by a "dragon router" · CPC title

• H01S5/1231

  Grating growth or overgrowth details · CPC title