Method for generating mid-infrared light

Abstract

A method for generating mid-infrared light by maintaining multiple quantum well (MQW) structures based on the alloy systems PbSrZ and PbSnZ, where Z is S, Se, or Te, at temperatures in the range of from about 5° C. to about 55° C. and pumping the MQW structures with a shorter wavelength continuous wave laser pump beam or with an electrical current is provided.

What is claimed is:  
     
         1 . A method for generating mid-infrared light comprising: providing a multiple quantum well structure including a plurality, n, of quantum wells, where n is in the range of from about 10 to about 70 and wherein each of said quantum wells further includes a Pb 1-y Sr y Z layer where Z is selected from the group consisting of S, Se, and Te, y is in the range of from about 0 atomic percent to about 15 atomic percent characterized by a layer thickness in the range of from about 2 nm to about 40 nm disposed between two Pb 1-x Sr x Z layers wherein x>y and x is in the range of from about 0 atomic percent to about 20 atomic percent and wherein each of said Pb 1-x Sr x Z layers is further characterized by a layer thickness in the range of from about 30 nm to 70 nm and a (111)-oriented BaF 2  substrate; maintaining said multiple quantum well structure at a temperature in the range of from about 5° C. to about 55° C.; and pumping said multiple quantum well structure with a continuous wave laser light source characterized by a laser light source wavelength shorter than a mid-infrared light wavelength so that mid-infrared light is emitted from said multiple quantum well structure.  
     
     
         2 . The method of  claim 1  wherein said laser light source wavelength is a wavelength in the range of from about 0.8 micron to about 3.0 micron.  
     
     
         3 . The method of  claim 1  wherein said step of pumping said multiple quantum well structure further includes providing a diode laser continuous wave laser light source.  
     
     
         4 . The method of  claim 1  wherein said mid-infrared light is emitted through said substrate.  
     
     
         5 . A method for generating mid-infrared light comprising: providing a multiple quantum well structure including a plurality, n, of quantum wells, where n is in the range of from about 10 to about 70 and wherein each of said quantum wells further includes a Pb 1-y Sn y Z layer where Z is selected from the group consisting of S, Se, and Te, y is in the range of from about 0 atomic percent to about 40 atomic percent characterized by a layer thickness in the range of from about 2 nm to about 40 nm disposed between two Pb 1-x Sr x Z layers wherein x<y and x is in the range of from about 0 atomic percent to about 20 atomic percent and wherein each of said Pb 1-x Sn x Z layers is further characterized by a layer thickness in the range of from about 30 nm to 70 nm and a (111)-oriented BaF 2  substrate; maintaining said multiple quantum well structure at a temperature in the range of from about 5° C. to about 55° C.; and pumping said multiple quantum well structure with a continuous wave laser light source characterized by a laser light source wavelength shorter than a mid-infrared light wavelength so that mid-infrared light is emitted from said multiple quantum well structure.  
     
     
         6 . The method of  claim 5  wherein said pump laser light source wavelength is a wavelength in the range of from about 0.8 micron to about 3.0 micron.  
     
     
         7 . The method of  claim 5  wherein said step of pumping said multiple quantum well structure further includes providing a diode laser continuous wave light source.  
     
     
         8 . The method of  claim 5  wherein said mid-infrared light is emitted through said substrate.  
     
     
         9 . A method for generating mid-infrared light comprising: providing a multiple quantum well structure including a plurality, n, of quantum wells, where n is in the range of from about 10 to about 70 and wherein each of said quantum wells further includes a Pb 1-y Sr y Z layer where Z is selected from the group consisting of S, Se, and Te, y is in the range of from about 0 atomic percent to about 15 atomic percent characterized by a layer thickness in the range of from about 2 nm to about 40 nm disposed between two Pb 1-x Sr x Z layers wherein x>y and x is in the range of from about 0 atomic percent to about 20 atomic percent and wherein each of said Pb 1-x Sr x Z layers is further characterized by a layer thickness in the range of from about 30 nm to 70 nm and a (111)-oriented BaF 2  substrate; placing said multiple quantum well structure between an n-type electrical contact layer and a p-type electrical contact layer; maintaining said multiple quantum well structure at a temperature in the range of from about 5° C. to about 55° C.; and pumping said multiple quantum well structure with a pump electrical current so that mid-infrared light is emitted from said multiple quantum well structure.  
     
     
         10 . The method of  claim 9  wherein said mid-infrared light is emitted through said substrate.  
     
     
         11 . A method for generating mid-infrared light comprising: providing a multiple quantum well structure including a plurality, n, of quantum wells, where n is in the range of from about 10 to about 70 and wherein each of said quantum wells further includes a Pb 1-y Sn y Z layer where Z is selected from the group consisting of S, Se, and Te, y is in the range of from about 0 atomic percent to about 40 atomic percent characterized by a layer thickness in the range of from about 2 nm to about 40 nm disposed between two Pb 1-x Sn x Z layers wherein x<y and x is in the range of from about 0 atomic percent to about 20 atomic percent and wherein each of said Pb 1-x Sn x Z layers is further characterized by a layer thickness in the range of from about 30 nm to 70 nm and a (111)-oriented BaF 2  substrate; placing said multiple quantum well structure between an n-type electrical contact layer and a p-type electrical contact layer; maintaining said multiple quantum well structure at a temperature in the range of from about 5° C. to about 55° C.; and pumping said multiple quantum well structure with a pump electrical current so that mid-infrared light is emitted from said multiple quantum well structure.  
     
     
         12 . The method of  claim 11  wherein said mid-infrared light is emitted through said substrate.