Single-photon nano-injection detectors

Abstract

Single-photon detectors, arrays of single-photon detectors, methods of using the single-photon detectors and methods of fabricating the single-photon detectors are provided. The single-photon detectors combine the efficiency of a large absorbing volume with the sensitivity of nanometer-scale carrier injectors, called “nanoinjectors”. The photon detectors are able to achieve single-photon counting with extremely high quantum efficiency, low dark count rates, and high bandwidths.

1 - 14 . (canceled) 
     
     
         15 . A photon detector comprising a semiconductor heterostructure, the semiconductor heterostructure comprising:
 (a) a photon absorber comprising a layer of photon absorbing material which absorbs photons to generate electron-hole pairs via an interband transition; and   (b) a carrier injector adapted to inject carriers of a first type into the photon absorber, the carrier injector comprising:
 (i) a layer of carrier injecting material capable of generating the carriers of the first type upon the application of a bias voltage; and 
 (ii) a carrier trap disposed between the layer of carrier injecting material and the layer of photon absorbing material, the carrier trap comprising a layer of potential barrier-forming material which forms a potential trap for carriers of a second type; 
   wherein the photon absorbing material, the carrier injecting material and the potential barrier-forming material have a band structure with a type II band alignment;   and further wherein a dimension of the layer of carrier injection material corresponding to a line passing across the surface of the layer of carrier injection material from one edge to an opposite facing edge and through the center of the layer of carrier injection material, the line parallel to the layers of the semiconductor heterostructure, is greater than 1 μm.   
     
     
         16 . The photon detector of  claim 15 , wherein the dimension of the layer of carrier injection material is greater than 5 μm. 
     
     
         17 . The photon detector of  claim 15 , wherein the dimension of the layer of carrier injection material is in the range of from greater than 1 μm to about 5 μm. 
     
     
         18 . The photon detector of  claim 15 , wherein the dimension of the layer of carrier injection material is the diameter of the layer of carrier injection material. 
     
     
         19 . The photon detector of  claim 15 , wherein a dimension of the layer of potential barrier-forming material corresponding to a line passing across the surface of the layer of potential barrier-forming material from one edge to an opposite facing edge and through the center of the layer of potential barrier-forming material, the line parallel to the layers of the semiconductor heterostructure is greater than the dimension of the layer of carrier injection material. 
     
     
         20 . A photon detector comprising a semiconductor heterostructure, the semiconductor heterostructure comprising:
 (a) a photon absorber comprising a layer of photon absorbing material which absorbs photons to generate electron-hole pairs via an interband transition; and   (b) a carrier injector adapted to inject carriers of a first type into the photon absorber, the carrier injector comprising:
 (i) a layer of carrier injecting material capable of generating the carriers of the first type upon the application of a bias voltage; and 
 (ii) a carrier trap disposed between the layer of carrier injecting material and the layer of photon absorbing material, the carrier trap comprising a layer of potential barrier-forming material which forms a potential trap for carriers of a second type; 
   wherein the photon absorbing material, the carrier injecting material and the potential barrier-forming material have a band structure with a type II band alignment;   and further wherein the photon detector is characterized by a bandwidth of greater than 100 MHz.   
     
     
         21 . The photon detector of  claim 20 , wherein the photon detector is characterized by a bandwidth of at least 1 GHz. 
     
     
         22 . The photon detector of  claim 20 , wherein the photon detector is characterized by a bandwidth in the range of from greater than 100 MHz to about 1 GHz. 
     
     
         23 . The photon detector of  claim 20 , further wherein a dimension of the layer of carrier injection material corresponding to a line passing across the surface of the layer of carrier injection material from one edge to an opposite facing edge and through the center of the layer of carrier injection material, the line parallel to the layers of the semiconductor heterostructure, is greater than 1 μm. 
     
     
         24 . The photon detector of  claim 23 , wherein the dimension of the layer of carrier injection material is greater than 5 μm. 
     
     
         25 . The photon detector of  claim 23 , wherein the dimension of the layer of carrier injection material is in the range of from greater than 1 μm to about 5 μm. 
     
     
         26 . The photon detector of  claim 25 , wherein the photon detector is characterized by a bandwidth in the range of from greater than 100 MHz to about 1 GHz. 
     
     
         27 . The photon detector of  claim 20 , wherein a dimension of the layer of potential barrier-forming material corresponding to a line passing across the surface of the layer of potential barrier-forming material from one edge to an opposite facing edge and through the center of the layer of potential barrier-forming material, the line parallel to the layers of the semiconductor heterostructure is greater than the dimension of the layer of carrier injection material. 
     
     
         28 . A photon detector comprising a semiconductor heterostructure, the semiconductor heterostructure comprising:
 (a) a photon absorber comprising a layer of photon absorbing material which absorbs photons to generate electron-hole pairs via an interband transition; and   (b) a carrier injector adapted to inject carriers of a first type into the photon absorber, the carrier injector comprising:
 (i) a layer of carrier injecting material capable of generating the carriers of the first type upon the application of a bias voltage; and 
 (ii) a carrier trap disposed between the layer of carrier injecting material and the layer of photon absorbing material, the carrier trap comprising a layer of potential barrier-forming material which forms a potential trap for carriers of a second type; 
   wherein the photon absorbing material, the carrier injecting material and the potential barrier-forming material have a band structure with a type II band alignment;   and further wherein the photon detector further comprises a layer of passivating material disposed between the layer of carrier injection material and the layer of potential barrier-forming material.   
     
     
         29 . The photon detector of  claim 28 , wherein the layer of passivating material does not produce an additional potential barrier in the conduction band of the band structure. 
     
     
         30 . The photon detector of  claim 28 , further wherein a dimension of the layer of carrier injection material corresponding to a line passing across the surface of the layer of carrier injection material from one edge to an opposite facing edge and through the center of the layer of carrier injection material, the line parallel to the layers of the semiconductor heterostructure, is greater than 1 μm. 
     
     
         31 . The photon detector of  claim 30 , wherein the dimension of the layer of carrier injection material is greater than 5 μm. 
     
     
         32 . The photon detector of  claim 30 , wherein the dimension of the layer of carrier injection material is in the range of from greater than 1 μm to about 5 μm. 
     
     
         33 . The photon detector of  claim 28 , wherein a dimension of the layer of potential barrier-forming material corresponding to a line passing across the surface of the layer of potential barrier-forming material from one edge to an opposite facing edge and through the center of the layer of potential barrier-forming material, the line parallel to the layers of the semiconductor heterostructure is greater than the dimension of the layer of carrier injection material.