Tunable VCSEL with combined gain and DBR mirror

Abstract

A vertical cavity surface emitting laser (VCSEL) has a shortened overall laser cavity by combining the gain section with a distributed Bragg reflector (DBR). The overall cavity length can be contracted by placing gain structures inside the DBR. This generally applies to a number of semiconductor material systems and wavelength bands, but this scheme is very well suited to the AlGaAs/GaAs material system with strained InGaAs quantum wells as a gain medium, for example.

What is claimed is: 
     
         1 . A vertical surface emitting laser, comprising:
 a distributed Bragg reflector; and   quantum wells located in the distributed Bragg reflector.   
     
     
         2 . The laser of  claim 1 , further comprising a deflectable membrane carrying a mirror defining an optical cavity of the laser. 
     
     
         3 . The laser of  claim 1 , wherein the quantum wells are located in shallow layers of the distributed Bragg reflector. 
     
     
         4 . The laser of  claim 1 , wherein the quantum wells located in the distributed Bragg reflector are fabricated in AlGaAs/GaAs. 
     
     
         5 . The laser of  claim 1 , wherein the quantum wells are located between high index layers and low index layers of the distributed Bragg reflector. 
     
     
         6 . The laser of  claim 1 , wherein the quantum wells are located in high index layers of the distributed Bragg reflector. 
     
     
         7 . The laser of  claim 1 , wherein the quantum wells are placed at antinodes of standing wave patterns in the laser. 
     
     
         8 . The laser of  claim 1 , further comprising eight or more quantum wells. 
     
     
         9 . The laser of  claim 1 , wherein the high index layers of the distributed Bragg reflector are thinner than the low index layers. 
     
     
         10 . The laser of  claim 1 , wherein the quantum wells are optically pumped. 
     
     
         11 . The laser of  claim 1 , wherein the quantum wells are electrically pumped. 
     
     
         12 . A vertical surface emitting laser system, comprising:
 a vertical surface emitting laser, including a distributed Bragg reflector and quantum wells located in the distributed Bragg reflector; and   a pump laser for optically pumping the quantum wells.   
     
     
         13 . The system of  claim 12 , wherein the laser further includes a deflectable membrane carrying a mirror defining an optical cavity of the laser. 
     
     
         14 . The system of  claim 12 , wherein the quantum wells are located in shallow layers of the distributed Bragg reflector. 
     
     
         15 . The system of  claim 12 , wherein the quantum wells located in the distributed Bragg reflector are fabricated in AGaAs/GaAs.