High-power single-mode triple-ridge waveguide semiconductor laser

Patent metadata

Field	Value
Publication number	US-12562550-B2
Application number	US-202217734894-A
Country	US
Kind code	B2
Filing date	May 2, 2022
Priority date	May 3, 2021
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

To achieve high-power single transverse mode laser, we here propose a supersymmetry (SUSY)-based triple-ridge waveguide semiconductor laser structure, which is composed of an electrically pumped main broad-ridge waveguide located in the middle and a pair of lossy auxiliary partner waveguides. The auxiliary partner waveguides are designed to provide dissipative modes that can phase match and couple with the higher-order modes in the main waveguide. By appropriately manipulating the gain-loss discrimination of the modes in the laser cavity, one can effectively suppress all the undesired higher-order transverse modes while keeping the fundamental one almost unaffected, thereby ensuring stable single-mode operation with a larger emitting aperture and accordingly a higher output power than a conventional single-transverse-mode ridge waveguide diode laser.

First claim

What is claimed is:

1 . A high-power single transverse mode laser, comprising:
a triple-ridge waveguide (TRW) structure, having a main waveguide in between a pair of auxiliary waveguides on respective lateral sides of the main waveguide, wherein the main waveguide is relatively wider than either of the auxiliary waveguides on either side thereof, to support high-order modes of the main waveguide, while optical loss is introduced by the two auxiliary waveguides, which two auxiliary waveguides are respectively configured to support guided modes that only couple with the high-order modes of the main waveguide, to filter out the high-order modes in the main waveguide, the pair of auxiliary waveguides are respectively separated from the main waveguide therebetween by a trench having the same trench width d, the trench has a trench depth which is less than about 1000 nm, the main waveguide has a width w M <20.0 μm, and supports at least three transverse electric (TE) modes TEM 0 , TEM 1 , and TEM 2 , and the TE mode 0 for one of the auxiliary waveguides (TEL 0 ) and the TE mode 0 for the other of the auxiliary waveguides (TER 0 ) are respectively chosen to couple with the TEM 1 and the TEM 2 modes.

2 . A high-power single transverse mode laser according to claim 1 , wherein the pair of auxiliary waveguides each have propagation constants β which match with those of guided modes associated with the main waveguide other than the main waveguide fundamental mode.

3 . A high-power single transverse mode laser according to claim 1 , wherein the trench width d is less than or equal to 2.0 μm.

4 . A high-power single transverse mode laser according to claim 3 , wherein the trench width d is in a range of from 1.35 μm to 0.9 μm.

5 . A high-power single transverse mode laser according to claim 1 , wherein the trench depth is about 900 nm.

6 . A high-power single transverse mode laser according to claim 3 , wherein the main waveguide has a width w M ≤20.0 μm, and each of the pair of auxiliary waveguides have widths w L (waveguide left width) and w R (waveguide right width) which are each ≤8.0 μm.

7 . A high-power single transverse mode laser according to claim 6 , wherein the trench width d is about 0.9 μm, the trench depth is about 900 nm, the main waveguide has a width w M about 12.0 μm, and each of the pair of auxiliary waveguides have widths w L about 4.9 μm and w R about 7.25 μm, respectively.

8 . A high-power single transverse mode laser according to claim 6 , wherein the trench width d is about 1.1 μm, the trench depth is about 900 nm, the main waveguide has a width w M about 10.0 μm, and each of the pair of auxiliary waveguides have widths w L about 3.95 μm and w R about 5.95 μm, respectively.

9 . A high-power single transverse mode laser according to claim 6 , wherein the effective index difference Δn eff between any of the ridges of the triple-ridge waveguide (TRW) structure and the trench is about 3.5×10 −3 .

10 . A high-power single transverse mode laser according to claim 1 , wherein:
the TRW structure includes an InGaAs/GaAs epitaxial wafer; and the laser operation wavelength λ is in a range of 0.95 μm to 1.05 μm.

11 . A methodology for providing a high-power single transverse mode laser, comprising:
providing a triple-ridge waveguide (TRW) structure, having a main waveguide in between a pair of auxiliary waveguides on respective lateral sides of the main waveguide, with the main waveguide relatively wider than either of the auxiliary waveguides on either side thereof, to support high-order modes of the main waveguide, and respectively configuring the two auxiliary waveguides to support guided modes that only couple with the high-order modes of the main waveguide, to introduce optical loss by the two auxiliary waveguides, which filters out the high-order modes in the main waveguide, wherein configuring the two auxiliary waveguides includes phase matching the two auxiliary waveguides with the higher-order modes in the main waveguide, such that the higher-order modes, except for the fundamental mode of the main waveguide, will split into symmetric (in-phase) and anti-symmetric (out-of-phase) supermode pairs, whereby the TRW structure effectively suppresses unwanted higher-order modes and ensures single-mode lasing in a relatively broader main ridge waveguide.

12 . A methodology according to claim 11 , wherein the pair of auxiliary waveguides each have propagation constants β which match with those of guided modes associated with the main waveguide other than the main waveguide fundamental mode.

13 . A methodology according to claim 11 , wherein the pair of auxiliary waveguides are respectively separated from the main waveguide therebetween by a trench having the same trench width d.

14 . A methodology according to claim 13 , wherein the trench width d is less than or equal to 2.0 μm.

15 . A methodology according to claim 14 , wherein the trench width d is in a range of from 1.35 μm to 0.9 μm.

16 . A methodology according to claim 13 , wherein the trench has a trench depth which is less than about 1000 nm.

17 . A methodology according to claim 16 , wherein the trench depth is about 900 nm.

18 . A methodology according to claim 14 , wherein the main waveguide has a width w M ≤20.0 μm, and each of the pair of auxiliary waveguides have widths w L (waveguide left width) and w R (waveguide right width) which are each ≤8.0 μm.

19 . A methodology according to claim 18 , wherein the trench width d is about 0.9 μm, the trench depth is about 900 nm, the main waveguide has a width w M about 12.0 μm, and each of the pair of auxiliary waveguides have widths w L about 4.9 μm and w R about 7.25 μm, respectively.

20 . A methodology according to claim 18 , wherein the trench width d is about 1.1 μm, the trench depth is about 900 nm, the main waveguide has a width w M about 10.0 μm, and each of the pair of auxiliary waveguides have widths w L about 3.95 μm and w R about 5.95 μm, respectively.

21 . A methodology according to claim 18 , wherein the effective index difference Δn eff between any of the ridges of the triple-ridge waveguide (TRW) structure and the trench is about 3.5×10 −3 .

22 . A methodology according to claim 16 , wherein:
the main waveguide has a width w M ≤20.0 μm, and supports at least three transverse electric (TE) modes TEM 0 , TEM 1 , and TEM 2 ; and wherein the TE mode 0 for one of the auxiliary waveguides (TEL 0 ) and the TE mode 0 for the other of the auxiliary waveguides (TER 0 ) are respectively chosen to couple with the TEM 1 and the TEM 2 modes.

23 . A methodology according to claim 11 , wherein:
the TRW structure includes an InGaAs/GaAs epitaxial wafer; and the laser operation wavelength λ is in a range of 0.95 μm to 1.05 μm.

24 . A methodology according to claim 11 , further including optimizing the respective auxiliary waveguide widths and trench widths by performing parameter sweeping based on two waveguide coupling.

25 . A methodology for providing an edge-emitting laser diode capable of high-power single-transverse-mode operation based on the principle of unbroken supersymmetry (SUSY), comprising:
providing a triple-ridge waveguide (TRW) structure, having a main ridge waveguide in between a pair of lossy auxiliary ridge waveguides, with the main ridge relatively wider than either of the auxiliary ridges; res

Assignees

• Univ Clemson
• Univ Clemson Res Foundation

Inventors

• Zhu Lin
• Zhao Xiaolei
• Zhu Yeyu
• Zeng Siwei

Classifications

• H01S5/0655

  Single transverse or lateral mode emission · CPC title

• H01S2301/18

  Semiconductor lasers with special structural design for influencing the near- or far-field · CPC title

• H01S2301/166

  Single transverse or lateral mode · CPC title

• H01S5/205

  Antiguided structures · CPC title

• H01S5/22 Primary

  having a ridge or stripe structure · CPC title