EP-VECSEL Emitter Array for Uniform Injection and Power Scaling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical pumping Vertical External Cavity Surface Emitting Lasers (VECSELs) face limitations in power scaling due to difficulties with carrier injection into the active region, restricting the achievable output power, whereas optically pumped VECSELs can easily scale by increasing the pumping area.
Innovation Solution
The design incorporates multiple pumping areas on a single VECSEL chip to create configurable Hermite Gaussian (HG) mode shapes, allowing for uniform carrier injection and efficient power scaling, along with the use of a piezoelectric element for coherent beam combining to form a desired output shape.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If electrical pumping is used in VECSELs, then device structure is simplified and electrical efficiency is improved, but achievable output power is limited due to carrier injection difficulties
Solution Approach 1:
The active region is divided into multiple independently controlled emitter regions (e.g., 2x2 array of emitters), each capable of being electrically pumped separately. This segmentation allows uniform carrier injection across the active region while maintaining electrical pumping efficiency, resolving the contradiction between electrical efficiency and output power limitation.
2Power
If pumping area is increased to scale power in VECSELs, then output power is improved, but carrier injection uniformity deteriorates
Solution Approach 1:
The active region is segmented into multiple discrete emitter regions that can be independently controlled. By increasing the number of emitters in the array rather than expanding a single emitter area, the total pumping area increases while maintaining uniform carrier injection characteristics across each individual emitter, thus preserving injection uniformity while scaling power.
Solution Approach 2:
Each emitter region is designed with optimized local properties for uniform carrier injection, while the overall array configuration enables power scaling. The local quality of each emitter maintains optimal injection characteristics, while the global arrangement achieves higher total power output.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables efficient power scaling and flexible beam shaping, overcoming previous limitations in electrical pumping VECSELs by allowing for the creation of desired HG modes and coherent beam combining, enhancing the device's output capabilities.
Implementation Method 1
the use of a piezoelectric element for coherent beam combining to form a desired output shape
Implementation Method 2
a first distributed Bragg reflector (DBR) disposed on the bottom contact... a second DBR disposed on the active region
Data Source
AI summary
An electrical pumping vertical external-cavity surface-emitting laser (EP-VECSEL) device. The device may comprise a bottom contact, a first distributed Bragg reflector (DBR) disposed on the bottom contact, and an active region comprising a plurality of emitters, disposed on the first DBR configured to accept an electrical current at multiple emitters on the active region such that the multiple emitters produce a plurality of lasers. The multiple emitters may be configured to form a desired Hermite Gaussian (HG) mode shape. The device may further comprise a second DBR disposed on the active region and a top contact disposed on the second DBR. The top contact may be shaped such that the plurality of lasers are directed through the top contact. The device may further comprise an array output coupler disposed optically in line with the top contact such that the plurality of lasers are directed into the array output coupler.