N-nary optical semiconductor transistor and an optical AND gate

Abstract

An N-nary photonic transistor (PT) based on a heterojunction optical semiconductor microstructure is presented. The PT has one control signal input, one data signal input, and one output. The lights for each input can be one of the wavelengths within the N number (N-nary) of predetermined lightwaves. The output light of the PT is determined by the inputs in accordance with the switching function of the PT. The PT can be used to construct either N-nary digital logic gates or binary Boolean logic gates. For the N-nary system, both the wavelength domain and intensity domain of the lights are used which forms a two dimensional logic system. An optical AND gate, which can be used as either N-nary or binary, is constructed using the current photonic transistor, which is also presented herein.

1 . An N-nary photonic transistor (PT) that uses both the wavelengths and the intensities of lights for digital information processing.  
   
   
       2 . The N-nary photonic transistor of  claim 1 , wherein said wavelengths of lights can be N, with N≧1 being the number of lightwaves used in the system, wherein N is determined by the requirement of the system and the bandwidth of the PT.  
   
   
       3 . The N-nary photonic transistor of  claim 1 , wherein said intensities of the lights can be either low, close to dark, or high, a predetermined light intensity.  
   
   
       4 . The N-nary photonic transistor of  claim 1 , comprising: 
 a transistor body, a control input port, a signal input port, an output port;    wherein the transistor body comprising a heterojunction traveling waveguide optical semiconductor microstructure that comprises a pair of electrodes, an active region of InGaAsP, a N-InP layer between the active region and the negative electrode, and a P-InP layer between the active region and the positive electrode.    wherein the control input takes the control light signal, the signal input port takes the data light signal, and the output port presents the output of the PT in accordance with the control and data inputs and obeys the following truth table:                                    Signal input   Control input   PT Output           0   0   0     0   λ i     0     λ j     0   λ j       λ j     λ i     0                                          
   
   
       5 . The N-nary photonic transistor of  claim 1 , wherein only one lightwave is used, N=1, it becomes a binary transistor that obeys the following truth table:  
     
       
         
               
               
               
             
                   
               
                   
               
                 Signal input 
                 Control input 
                 PT Output 
               
                   
               
                 0 
                 0 
                 0 
               
                 0 
                 1 
                 0 
               
                 1 
                 0 
                 1 
               
                 1 
                 1 
                 0 
               
                   
               
                   
               
           
              
              
              
              
             
             
              
              
              
              
              
              
             
          
         
       
     
   
   
       6 . An N-nary optical AND (O-AND) gate constructed using the herein disclosed photonic transistor, comprising: 
 an O-AND gate body, a control input port, a signal input port, an output port;    wherein the O-AND body comprising two photonic transistors, two optical semiconductor amplifiers and a phase shifter;    wherein the control input takes the control light signal, the signal input port takes the data light signal, and the output port presents the output of the O-AND in accordance with the control and data inputs and obeys the following truth table:                                    Signal input   Control input   O-AND gate Output           0   0   0     0   λ i     0     λ j     0   0     λ j     λ i     λ j                                            
   
   
       7 . The N-nary O-AND of  claim 6 , wherein only one lightwave is used, N=1, it becomes a binary O-AND that obeys the Boolean logic shown in the following truth table:  
     
       
         
               
               
               
             
                   
               
                   
               
                 Signal input 
                 Control input 
                 O-AND agte Output 
               
                   
               
                 0 
                 0 
                 0 
               
                 0 
                 1 
                 0 
               
                 1 
                 0 
                 0 
               
                 1 
                 1 
                 1