Lasing output based on varying modal index

Patent metadata

Field	Value
Publication number	US-2016336708-A1
Application number	US-201415110429-A
Country	US
Kind code	A1
Filing date	Feb 28, 2014
Priority date	Feb 28, 2014
Publication date	Nov 17, 2016
Grant date	—

Abstract

An example device in accordance with an aspect of the present disclosure includes a ring waveguide and bus waveguide. The ring waveguide has a first coupled portion associated with a first modal index, and the bus waveguide includes a second coupled portion associated with a second modal index. The second coupled portion is evanescently coupleable to the first coupled portion. A laser outcoupling and associated lasing output of the device is variable based on varying a difference between the first modal index and the second modal index to vary coupling between the first coupled portion and the second coupled portion, without varying modal indices of non-coupled portions of the ring waveguide and bus waveguide.

First claim

What is claimed is:

1 . A device comprising:
a ring waveguide having a first coupled portion associated with a first modal index; and a bus waveguide having a second coupled portion, associated with a second modal index, wherein the second coupled portion is evanescently coupleable to the first coupled portion; wherein a laser outcoupling and associated lasing output of the device is variable based on varying a difference between the first modal index and the second modal index to vary coupling between the first coupled portion and the second coupled portion, without varying modal indices of non-coupled portions of the ring waveguide and bus waveguide.

2 . The device of claim 1 , wherein the ring waveguide is to serve as a laser cavity based on resonance of the ring waveguide.

3 . The device of claim 1 , further comprising an output waveguide coupled to the ring waveguide based on a third coupled portion of the ring waveguide; wherein the bus waveguide is to serve as a laser cavity based on resonance of the bus waveguide; wherein the ring waveguide is passive and is to couple lasing output from the bus waveguide to the output waveguide.

4 . The device of claim 1 , wherein the bus waveguide is a conformal waveguide that is curved corresponding to coupling with the ring waveguide.

5 . The device of claim 1 , wherein the difference between the first modal index and the second modal index is achieved based on changing an index of a cladding of at least one of: the first coupled portion of the ring waveguide, and the second coupled portion of the bus waveguide.

6 . The device of claim 1 , wherein the ring waveguide is coplanar with the bus waveguide.

7 . The device of claim 1 , wherein the ring waveguide is non-coplanar with, and vertically displaced relative to, the bus waveguide.

8 . The device of claim 1 , further comprising heater to apply heat to vary the difference between the first modal index and the second modal index.

9 . The device of claim 1 , further comprising a capacitor structure including a dielectric layer sandwiched by semiconductor layers of the device, to apply electrical carriers to vary the difference between the first modal index and the second modal index.

10 . The device of claim 1 , further comprising a quantum well structure embedded in a layer of the device, to apply an electro-optical effect to vary the difference between the first modal index and the second modal index.

11 . A system comprising:
a ring waveguide having a first coupled portion associated with a first modal index; a bus waveguide having a second coupled portion, associated with a second modal index, wherein the second coupled portion is evanescently coupled to the first coupled portion; and a controller to vary a laser outcoupling and associated lasing output of the system based on varying a difference between the first modal index and the second modal index to vary coupling between the first coupled portion and the second coupled portion, without varying modal indices of non-coupled portions of the ring waveguide and bus waveguide.

12 . The system of claim 10 , wherein the controller is to vary the second modal index of the second coupled portion of the bus waveguide without varying the first modal index of the ring waveguide, to vary the difference between the first modal index and the second modal index.

13 . The system of claim 10 , wherein the controller is to vary the first modal index of the ring waveguide without varying the second modal index of the bus waveguide, to vary the difference between the first modal index and the second modal index.

14 . The system of claim 10 , wherein the controller is a modulation actuator to vary modal indices based on at least one of heat tuning, electrical tuning, mechanical tuning, acoustic tuning, and magnetic tuning.

15 . A method, comprising:
applying an optical signal to at least one of a ring waveguide and a bus waveguide; varying a difference between a first modal index associated with a first coupled portion of the ring waveguide, and a second modal index associated with a second coupled portion of the bus waveguide, wherein the second coupled portion is evanescently coupled to the first coupled portion; and varying a laser outcoupling and associated lasing output based on varying the difference between the first modal index and the second modal index, without varying modal indices of non-coupled portions of the ring waveguide and bus waveguide.

Assignees

• Hewlett Packard Entpr Dev Lp

Inventors

• Liang Di

Classifications

• H01S3/1028

  by controlling the temperature · CPC title

• H01S3/102

  by controlling the active medium, e.g. by controlling the processes or apparatus for excitation (H01S3/13 takes precedence) · CPC title

• H01S3/0637

  Integrated lateral waveguide, e.g. the active waveguide is integrated on a substrate made by Si on insulator technology (Si/SiO2) · CPC title

• H01S3/083 Primary

  Ring lasers {(fibre ring lasers H01S3/06791)} · CPC title

• H01S5/1225

  with a varying coupling constant along the optical axis · CPC title