{
"metadata": {
"name": "",
"signature": "sha256:bd93f1663667ee07f8c4bdf99d82cf6a60f9abb18ce0de8906898bec0afa103e"
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"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 6 - Optical Sources"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.3.1 :Pg 6.7"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# variable initialisation\n",
"x=0.07\n",
"\n",
"# calculations\n",
"Eg=1.424+1.266*x+0.266*math.pow(x,2)\n",
"lamda=1.24/Eg # computing wavelength\n",
"\n",
"# Results\n",
"print '%s %.3f %s' %(\"\\nWavlength is \",lamda,\"micrometer \")\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Wavlength is 0.819 micrometer \n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.3.2 : Pg 6.12"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"n=1.7 #refractive index\n",
"L=5*pow(10,-2) #distance between mirror\n",
"c=3*pow(10,8) #speed of light\n",
"lamda=0.45*pow(10,-6) #wavelength\n",
"\n",
"# Calculations\n",
"k=2*n*L/lamda #computing number of modes\n",
"delf=c/(2*n*L) #computing mode separation\n",
"delf=delf*pow(10,-9)\n",
"\n",
"# Results\n",
"print '%s %.2e %s %.2f %s'%(\"\\nNumber of modes are \",k,\"\\nFrequency separation is \",delf,\" GHz.\")\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Number of modes are 3.78e+05 \n",
"Frequency separation is 1.76 GHz.\n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.21.1 : Pg 6.59"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"tr=50.0 #radiative recombination lifetime\n",
"tnr=85.0 #non-radiative recombination lifetime\n",
"h=6.624*pow(10,-34) #plank's constant\n",
"c=3*pow(10,8) #speed of light\n",
"q=1.6*pow(10,-19) #charge of electron\n",
"i=35*pow(10,-3) #current\n",
"lamda=0.85*pow(10,-6) #wavelength\n",
"\n",
"# Calculations\n",
"t=tr*tnr/(tr+tnr) #computing total recombination time\n",
"eta=t/tr #computing internal quantum efficiency\n",
"Pint=eta*h*c*i/(q*lamda) #computing internally generated power\n",
"Pint=Pint*pow(10,3)\n",
"\n",
"# Results\n",
"\n",
"print '%s %.2f %s %.3f %s %.1f %s' %(\"\\nTotal recombinaiton time is \",t,\" ns.\\nInternal quantum efficiency is \",eta,\".\\nInternally generated power is \",Pint,\" mW.\")\n",
"\n",
"#answer in the book for Internal quantum efficiency is 0.629, deviation of 0.001.\n",
"#answer in the book for Internally generated power is 32.16 mW, deviation of 0.04 mW.\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Total recombinaiton time is 31.48 ns.\n",
"Internal quantum efficiency is 0.630 .\n",
"Internally generated power is 32.2 mW.\n"
]
}
],
"prompt_number": 12
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.21.2 : Pg 6.59"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"tr=30.0 #radiative recombination lifetime\n",
"tnr=100.0 #non-radiative recombination lifetime\n",
"h=6.624*pow(10,-34) #plank's constant\n",
"c=3*pow(10,8) #speed of light\n",
"q=1.6*pow(10,-19) #charge of electron\n",
"i=40*pow(10,-3) #current\n",
"lamda=1310*pow(10,-9) #wavelength\n",
"\n",
"# Calculations\n",
"t=tr*tnr/(tr+tnr) #computing total recombination time\n",
"eta=t/tr #computing internal quantum efficiency\n",
"Pint=eta*h*c*i/(q*lamda) #computing internally generated power\n",
"Pint=Pint*pow(10,3)\n",
"\n",
"print '%s %.2f %s %.3f %s %.2f %s' %(\"\\nTotal recombinaiton time is \",t,\" ns.\\nInternal quantum efficiency is \",eta,\".\\nInternally generated power is \",Pint,\" mW.\")\n",
"\n",
"#answer in the book for Total recombinaiton time is 23.07 ns, deviation of 0.01ns.\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Total recombinaiton time is 23.08 ns.\n",
"Internal quantum efficiency is 0.769 .\n",
"Internally generated power is 29.17 mW.\n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.21.3 : Pg 6.60"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Example 6.21.3 page 6.60\n",
"\n",
"import math\n",
"# Variable initialisation\n",
"\n",
"tr=50.0 #radiative recombination lifetime\n",
"tnr=110.0 #non-radiative recombination lifetime\n",
"h=6.624*pow(10,-34) #plank's constant\n",
"c=3*pow(10,8) #speed of light\n",
"q=1.6*pow(10,-19) #charge of electron\n",
"i=40*pow(10,-3) #current\n",
"lamda=0.87*pow(10,-6) #wavelength\n",
"\n",
"# Calculations\n",
"t=tr*tnr/(tr+tnr) #computing total recombination time\n",
"eta=t/tr #computing internal quantum efficiency\n",
"Pint=eta*h*c*i/(q*lamda) #computing internally generated power\n",
"Pint=Pint*pow(10,3)\n",
"\n",
"print '%s %.2f %s %.4f %s %.2f %s' %(\"\\nTotal recombinaiton time is \",t,\"ns.\\nInternal quantum efficiency is \",eta,\".\\nInternally generated power is \",Pint,\"mW.\")\n",
"\n",
"#answers in the book with slight deviaitons\n",
"#Total recombinaiton time is 34.37 ns, deviation of 0.01ns.\n",
"#Internal quantum efficiency is 0.6874, deviaiton of 0.0001.\n",
"#Internally generated power is 39.24 mW, deviation of 0.02mW.\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Total recombinaiton time is 34.38 ns.\n",
"Internal quantum efficiency is 0.6875 .\n",
"Internally generated power is 39.26 mW.\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.22.1 : Pg 6.68"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"f1=10*pow(10,6) #frequency\n",
"f2=100*pow(10,6)\n",
"t=4*pow(10,-9)\n",
"Pdc=280*pow(10,-6) #optincal output power\n",
"\n",
"# Calculations\n",
"w1=2*math.pi*f1 #computing omega\n",
"Pout1=Pdc*pow(10,6)/(math.sqrt(1+pow((w1*t),2))) #computing output power\n",
"\n",
"w2=2*math.pi*f2 #computing omega\n",
"Pout2=Pdc*pow(10,6)/(math.sqrt(1+pow((w2*t),2))) #computing output power\n",
"\n",
"print '%s %.2f %s %.2f %s' %(\"Ouput power at 10 MHz is \",Pout1,\"microwatt.\\nOuput power at 100 MHz is \",Pout2,\"microwatt.\\nConclusion when device is drive at higher frequency the optical power reduces.\\nNOTE - calculation error. In the book square term in the denominator is not taken.\")\n",
"BWopt = math.sqrt(3)/(2*math.pi*t)\n",
"BWelec = BWopt/math.sqrt(2)\n",
"BWopt=BWopt*pow(10,-6)\n",
"BWelec=BWelec*pow(10,-6)\n",
"\n",
"print '%s %.2f %s %.2f %s' %(\"\\n3 dB optical power is \",BWopt,\" MHz.\\n3 dB electrical power is \",BWelec,\" MHz.\")\n",
"\n",
"\n",
"#calculation error. In the book square term in the denominater is not taken.\n",
"#answers in the book - \n",
"#Ouput power at 10 MHz is 228.7 microwatt.(incorrect)\n",
"#Ouput power at 100 MHz is 175 microwatt.(incorrect)\n",
"#3 dB optical power is 68.8 MHz, deviation of 0.12\n",
"#3 dB electrical power is 48.79 MHz, deviation of 0.06 \n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Ouput power at 10 MHz is 271.55 microwatt.\n",
"Ouput power at 100 MHz is 103.52 microwatt.\n",
"Conclusion when device is drive at higher frequency the optical power reduces.\n",
"NOTE - calculation error. In the book square term in the denominator is not taken.\n",
"\n",
"3 dB optical power is 68.92 MHz.\n",
"3 dB electrical power is 48.73 MHz.\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.22.2 : Pg 6.69"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"n1=3.5 #refractive index\n",
"n=1 #refractive index of air\n",
"F=0.69 #transmission factor\n",
"\n",
"# Calculations\n",
"eta = 100*pow((n1*pow((n1+1),2)),-1) #computing eta\n",
"\n",
"# Results\n",
"print '%s %.1f %s' %(\"\\neta external is \",eta,\" percent i.e. small fraction of intrnally generated opticalpower is emitted from the device.\")\n",
"print \"\\n\\n OR we can also arrive at solution,\\n\" \n",
"\n",
"r= 100*F*pow(n,2)/(4*pow(n1,2)) #computing ratio of Popt/Pint\n",
"\n",
"print '%s %.1f %s' %(\"\\n Popt/Pint is \",r,\"percent\")\n",
"\n",
"print \"\\nNOTE - printing mistake at final answer.\\nThey have printed 40 percent it should be 1.4 percent\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"eta external is 1.4 percent i.e. small fraction of intrnally generated opticalpower is emitted from the device.\n",
"\n",
"\n",
" OR we can also arrive at solution,\n",
"\n",
"\n",
" Popt/Pint is 1.4 percent\n",
"\n",
"NOTE - printing mistake at final answer.\n",
"They have printed 40 percent it should be 1.4 percent\n"
]
}
],
"prompt_number": 16
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 6.22.3 : Pg 6.73"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"# Variable initialisation\n",
"beta0=1.85*pow(10,7)\n",
"T=293 #temperature\n",
"k=1.38*pow(10,-23) #Boltzman constant\n",
"Ea=0.9*1.6*pow(10,-19)\n",
"theta=0.65 #threshold\n",
"\n",
"# Calculations\n",
"betar=beta0*pow(math.e,(-Ea/(k*T)))\n",
"t=-math.log(theta)/betar\n",
"\n",
"# Result\n",
"print '%s %.2e %s %.1e %s' %(\"\\nDegradation rate is \",betar,\" per hour.\\nOperating lifetime is \",t,\" hour.\")\n",
"\n",
"#answer in the book for Degradation rate is 6.4e-09 per hour, deviation of 0.08e-9\n",
"#answer in the book for Operating lifetime is 6.7e+07 hour, deviaiton of 0.1e1\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"Degradation rate is 6.32e-09 per hour.\n",
"Operating lifetime is 6.8e+07 hour.\n"
]
}
],
"prompt_number": 17
}
],
"metadata": {}
}
]
}