{ "metadata": { "name": "", "signature": "sha256:1c5868fa547e8a659e03148d4a7bf0c9a34282713a490e0b68c5b0aa98a2f7e8" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter03:Optical Sources and Transmitters" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.1:Pg-3.10" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "x= 0.07 \n", "Eg= 1.424+1.266*x+0.266*x**2 \n", "lamda= 1.24/Eg \n", "print \" The emitted wavelength in um =\",round(lamda,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The emitted wavelength in um = 0.82\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.2:Pg-3.10" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "x= 0.26 \n", "y=0.57 \n", "Eg= 1.35-0.72*y+0.12*y**2 \n", "lamda = 1.24/Eg \n", "print \" The wavelength emitted in um =\",round(lamda,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The wavelength emitted in um = 1.27\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.3:Pg-3.12" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "Tr = 60*10**-9 # radiative recombination time\n", "Tnr= 90*10**-9 # non radiative recomb time\n", "I= 40*10**-3 # current\n", "t = Tr*Tnr/(Tr+Tnr) # total recomb time\n", "t=t*10**9 # Converting in nano secs...\n", "print \" The total carrier recombination life time in ns =\",int(t) \n", "t=t/10**9 \n", "h= 6.625*10**-34 # plancks const\n", "c= 3*10**8 \n", "q=1.602*10**-19 \n", "lamda= 0.87*10**-6 \n", "Pint=(t/Tr)*((h*c*I)/(q*lamda)) \n", "Pint=Pint*1000 # converting inmW...\n", "print \" \\n\\nThe Internal optical power in mW =\",round(Pint,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The total carrier recombination life time in ns = 36\n", " \n", "\n", "The Internal optical power in mW = 34.22\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.4:Pg-3.13" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "lamda = 1310*10**-9 \n", "Tr= 30*10**-9 \n", "Tnr= 100*10**-9 \n", "I= 40*10**-3 \n", "t= Tr*Tnr/(Tr+Tnr) \n", "t=t*10**9 # converting in nano secs...\n", "print \" Bulk recombination life time in ns =\",round(t,2) \n", "t=t/10**9 \n", "n= t/Tr \n", "print \" \\n\\nInternal quantum efficiency =\",round(n,3) \n", "h= 6.625*10**-34 # plancks const\n", "c= 3*10**8 \n", "q=1.602*10**-19 \n", "Pint=(0.769*h*c*I)/(q*lamda)*1000 \n", "print \" \\n\\nThe internal power level in mW =\",round(Pint,3) \n", "print \" \\n\\n***NOTE: Internal Power wrong in text book.. Calculation Error..\" \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Bulk recombination life time in ns = 23.08\n", " \n", "\n", "Internal quantum efficiency = 0.769\n", " \n", "\n", "The internal power level in mW = 29.131\n", " \n", "\n", "***NOTE: Internal Power wrong in text book.. Calculation Error..\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.5:Pg-3.14" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "nx= 3.6 \n", "TF= 0.68 \n", "n= 0.3 \n", " # Pe=Pint*TF*1/(4*nx**2) \n", " # ne= Pe/Px*100 ..eq0\n", " # Pe = 0.013*Pint # Eq 1\n", " # Pint = n*P # Eq 2\n", " # substitute eq2 and eq1 in eq0\n", "ne = 0.013*0.3*100 \n", "print \" The external Power efficiency in % =\",round(ne,3) \n", " # Wrongly printed in textbook. it should be P instead of Pint in last step\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The external Power efficiency in % = 0.39\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.6:Pg-3.15" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "lamda= 0.85*10**-6 \n", "Nint = 0.60 \n", "I= 20*10**-3 \n", "h= 6.625*10**-34 # plancks const\n", "c= 3*10**8 \n", "e=1.602*10**-19 \n", "Pint = Nint*h*c*I/(e*lamda) \n", "print \" The optical power emitted in W =\",round(Pint,4) \n", "\n", "TF= 0.68 \n", "nx= 3.6 \n", "Pe= Pint*TF/(4*nx**2)*1000000 \n", "print \" \\n\\nPower emitted in the air in uW =\",round(Pe,1) \n", "Pe=Pe/1000000 \n", "Nep=Pe/Pint*100 \n", "print \" \\n\\nExternal power efficiency in % =\",round(Nep,1) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The optical power emitted in W = 0.0175\n", " \n", "\n", "Power emitted in the air in uW = 229.7\n", " \n", "\n", "External power efficiency in % = 1.3\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.7:Pg-3.16" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "lamda = 0.87*10**-6 \n", "Tr= 50*10**-9 \n", "I= 0.04 \n", "Tnr= 110*10**-9 \n", "t= Tr*Tnr/(Tr+Tnr) \n", "t=t*10**9 # converting in ns...\n", "print \" Total carrier recombination life time in ns =\",round(t,2) \n", "t=t/10**9 \n", "h= 6.625*10**-34 # plancks const\n", "c= 3*10**8 \n", "q=1.602*10**-19 \n", "n= t/Tr \n", "print \" \\n\\nThe efficiency in % \",round(n,3) \n", "Pint=(n*h*c*I)/(q*lamda)*1000 \n", "print \" \\n\\nInternal power generated in mW =\",round(Pint,2) \n", "print \" \\n\\n***NOTE- Internal Power wrong in book... \"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Total carrier recombination life time in ns = 34.38\n", " \n", "\n", "The efficiency in % 0.688\n", " \n", "\n", "Internal power generated in mW = 39.22\n", " \n", "\n", "***NOTE- Internal Power wrong in book... \n" ] } ], "prompt_number": 15 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.2.8:Pg-3.16" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", " \n", "\n", "V= 2 \n", "I= 100*10**-3 \n", "Pc= 2*10**-3 \n", "P= V*I \n", "Npc= Pc/P*100 \n", "print \" The overall power conversion efficiency in % =\",int(Npc) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The overall power conversion efficiency in % = 1\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.1:Pg-3.25" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", "\n", "r1= 0.32 \n", "r2= 0.32 \n", "alpha= 10 \n", "L= 500*10**-4 \n", "temp=math.log(1/(r1*r2)) \n", "Tgth = alpha + (temp/(2*L)) \n", "print \" The optical gain at threshold in /cm =\",round(Tgth,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The optical gain at threshold in /cm = 32.79\n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.2:Pg-3.27" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", " \n", "n= 3.7 \n", "lamda = 950*10**-9 \n", "L= 500*10**-6 \n", "c= 3*10**8 \n", "DELv = c/(2*L*n)*10*10**-10 # converting in GHz...\n", "print \" The frequency spacing in GHz =\",int(DELv) \n", "DEL_lamda= lamda**2/(2*L*n)*10**9 # converting to nm..\n", "print \" \\n\\nThe wavelength spacing in nm =\",round(DEL_lamda,2) \n", "\n", "print \" \\n\\n***NOTE- The value of wavelength taken wrongly in book\" \n", " # value of lamda taken wrongly while soving for DEL_LAMDA inthe book..\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The frequency spacing in GHz = 81\n", " \n", "\n", "The wavelength spacing in nm = 0.24\n", " \n", "\n", "***NOTE- The value of wavelength taken wrongly in book\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.3:Pg-3.30" ] }, { "cell_type": "code", "collapsed": false, "input": [ " #Given\n", " \n", "L= 0.04 \n", "n= 1.78 \n", "lamda= 0.55*10**-6 \n", "c= 3*10**8 \n", "q= 2*n*L/lamda \n", "q=q/10**5 \n", "print \" Number of longitudinal modes =\",round(q,2),\"x 10^5\" \n", "del_f= c/(2*n*L) \n", "del_f=del_f*10**-9 \n", "print \" \\n\\nThe frequency seperation in GHz =\",round(del_f,1) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Number of longitudinal modes = 2.59 x 10^5\n", " \n", "\n", "The frequency seperation in GHz = 2.1\n" ] } ], "prompt_number": 20 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.4:Pg-3.33" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "Nt= 0.18 \n", "V= 2.5 \n", "Eg= 1.43 \n", "Nep= Nt*Eg*100/V \n", "print \" The total efficiency in % =\",round(Nep,3) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The total efficiency in % = 10.296\n" ] } ], "prompt_number": 22 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.5:Pg-3.33" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "n= 3.6 \n", "BETA= 21*10**-3 \n", "alpha= 10 \n", "L= 250*10**-4 \n", "\n", "r= (n-1)**2/(n+1)**2 \n", "Jth= 1/BETA *( alpha + (math.log(1/r)/L)) \n", "Jth=Jth/1000 # converting for displaying...\n", "print \" The threshold current density =\",round(Jth,3),\"x 10**3\" \n", "Jth=Jth*1000 \n", "Ith =Jth*250*100*10**-8 \n", "Ith=Ith*1000 # converting into mA...\n", "print \" \\n\\nThe threshold current in mA =\",round(Ith,1) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The threshold current density = 2.65 x 10**3\n", " \n", "\n", "The threshold current in mA = 662.4\n" ] } ], "prompt_number": 24 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.3.6:Pg-3.34" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "\n", "T= 305.0 \n", "T0 = 160.0 \n", "T1= 373.0\n", "\n", "Jth_32 = exp(T/T0) \n", "Jth_100 = exp(T1/T0) \n", "R_j = Jth_100/Jth_32 \n", "print \" Ratio of current densities at 160K is =\",round(R_j,2) \n", "print \" \\n\\n***NOTE- Wrong in book...\\nJth(100) calculated wrongly...\" \n", "To = 55 \n", "Jth_32_new = exp(T/To) \n", "Jth_100_new = exp(T1/To) \n", "R_j_new = Jth_100_new/Jth_32_new \n", "print \" \\n\\nRatio of current densities at 55K is \",round(R_j_new,2) \n", " # wrong in book...\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Ratio of current densities at 160K is = 1.53\n", " \n", "\n", "***NOTE- Wrong in book...\n", "Jth(100) calculated wrongly...\n", " \n", "\n", "Ratio of current densities at 55K is 3.44\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.4.1:Pg-3.42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", "\n", "Bo= 150 \n", "rs= 35*10**-4 \n", "a1= 25*10**-6 \n", "NA= 0.20 \n", "a2= 50*10**-6 \n", "\n", "Pled = (a1/rs)**2 * (math.pi**2*rs**2*Bo*NA**2) \n", "Pled=Pled*10**10 # converting in uW...\n", "print \" The power coupled inthe fibre in uW =\",int(Pled) \n", "Pled_new = (math.pi**2*rs**2*Bo*NA**2) \n", "Pled_new=Pled_new*10**6 # converting in uW...\n", "print \" \\n\\nThe Power coupled for case 2 in uW =\",round(Pled_new,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The power coupled inthe fibre in uW = 370\n", " \n", "\n", "The Power coupled for case 2 in uW = 725.42\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.4.2:Pg-3.43" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", "n= 1.48 \n", "n1= 3.6 \n", "R= (n1-n)**2/(n1+n)**2 \n", "print \" The Fresnel Reflection is \",round(R,4) \n", "L= -10*math.log10(1-R) \n", "print \" \\n\\nPower loss in dB =\",round(L,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The Fresnel Reflection is 0.1742\n", " \n", "\n", "Power loss in dB = 0.83\n" ] } ], "prompt_number": 28 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.4.3:Pg-3.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", "\n", "NA= 0.20 \n", "Bo= 150 \n", "rs= 35*10**-6 \n", "Pled = math.pi**2*rs**2*Bo*NA**2 \n", "Pled=Pled*10**10 # convertin in uW for displaying...\n", "print \" The optical power coupled in uW =\",round(Pled,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The optical power coupled in uW = 725.42\n" ] } ], "prompt_number": 29 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.4.4:Pg-3.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", "\n", "n1= 1.5 \n", "n=1 \n", "R= (n1-n)**2/(n1+n)**2 \n", "L= -10*math.log10(1-R) \n", " # Total loss is twice due to reflection\n", "L= L+L \n", "print \" Total loss due to Fresnel Reflection in dB =\",round(L,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Total loss due to Fresnel Reflection in dB = 0.35\n" ] } ], "prompt_number": 30 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3.4.5:Pg-3.51" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "import math\n", " \n", "n1= 1.5 \n", "n=1.0 \n", "y=5.0 \n", "a= 25.0 \n", "temp1=(1-(y/(2*a)**2))**0.5 \n", "temp1=temp1*(y/a) \n", "temp=2*math.acos(0.9996708) # it should be acos(0.1) actually... due to approximations\n", " \n", " # answer varies a lot... \n", "temp=math.degrees(temp)-temp1 \n", " # temp=temp \n", "tem= 16*(1.5**2)/(2.5**4) \n", "tem=tem/math.pi \n", "temp=temp*tem \n", "Nlat= temp \n", "print \" The Coupling efficiency is =\",round(Nlat,3) \n", "L= -10*math.log10(Nlat) \n", "print \" \\n\\nThe insertion loss in dB =\",round(L,2) \n", "temp1=(1-(y/(2*a)**2))**0.5 \n", "temp1=temp1*(y/a) \n", "temp=2*math.acos(0.9996708) # it should be acos(0.1) actually... due to approximations\n", " # answer varies a lot... \n", "temp=math.degrees(temp)-temp1 \n", "temp=temp/math.pi \n", "N_new =temp \n", "print \" \\n\\nEfficiency when joint index is matched =\",round(N_new,3) \n", "L_new= -10*math.log10(N_new) \n", "print \" \\n\\nThe new insertion loss in dB =\",round(L_new,2) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " The Coupling efficiency is = 0.804\n", " \n", "\n", "The insertion loss in dB = 0.95\n", " \n", "\n", "Efficiency when joint index is matched = 0.872\n", " \n", "\n", "The new insertion loss in dB = 0.59\n" ] } ], "prompt_number": 39 } ], "metadata": {} } ] }