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Thin films, light at interface
* Thin film calculation
* Reflectance of complex index material

 General photonic
* Index of refraction: fixed ratio, variable ratio
* Gaussian beam propagation, Polarization matrices
* Optical Parametric Oscillator
* Coherence length, Finesse & FSR
* Beam deflection by substrate
 		Conversions and equivalencies
* Differential frequency , Differential wavelength
* Photon energy (eV) -- wavelength (nm)-- frequency(Hz) -- wave number (cm-1)
* Permittivity to index & vice versa
* Carbon footprint of calculation

If you have questions for luxpop or if you have references, suggestions, or answers to questions, please contact luxpop. Old miniblog entries, Code and Verifications.

Index of Refraction
Substance:       l:nm        temperature (certain substances only) deg C     

Special variable compound category: return the index of refraction of variable atomic content compound materials at a given wavelength, l (nm), and material content proportion, x. For example, you can specify the aluminium content in AlGaAs. Note that there may not be full coverage of all x or lambda values.

  • For quaternary materials such as In1-xGaxAsyP1-y or AlGaInAs, Luxpop assumes there is a lattice match to InP. As such, there is no need to specify a value for y since entering a value for x will force a value of y.
  • For H2SO4 (sulfuric acid) and HNO3 (nitric acid), x relates to the wt % of these substances in water. e.g. x=0.4 for H2SO4 means a 40% ratio of H2SO4 by weight in an aqueous solution. H2SO4 and HNO3 are available down to stratospheric temperatures. Variable-compound ternary H2SO4-HNO3-H2O solutions also are given  with H2SO4.

    • Substance:     l: nm       x:      temperature:  deg C    

    Light at interface

    Thin film stack model: reflectivity/transmissivity online calculation for light incident at an arbitrary angle on a thin film stack.
    The algorithm returns full reflected/transmitted field, power, and phase information for incident TE (perp) and TM (para) waves.
    There are up several sets of information to be entered:
      1 Incident angle, centre wavelength, wavelength sweep range, and number of points(max 20) to compute across the wavelength sweep range.
      2 Complex index of refraction of incident medium (n,k). For air, n=1 and k=0 is a good approximation.
      3 Thin film stack. Enter stack information using the following notation, where the top film is closest to the incident medium (see examples below):
      Fixed index on each layer: notation Fully dispersive calculation: notation
        thickness1, n1,k1
        thickness2, n2,k2
        thickness3, n3,k3
        thickness1, {Material1}
        thickness2, n2,k2
        thickness3, {Material3}

        Deposition materials currently available are: Ag,Al,Au,GaAs,Ni,SiO2,
        Si3N4        .
        Contact Luxpop to get your favourite material added.
        NOTE: if '{ }' chracters do not work on your system, use '( )' characters.
      4 Complex index of refraction of substrate (ns,ks): either enter a fixed value OR leave the ns,ks fields blank and choose a substrate material for a fully dispersive calculation.
        Here are some examples of thin film stacks. Feel free to cut and paste into the "3" box below. The first example uses fixed index layers, the second example shows how to enter materials
    Example#1: Fixed index layers(Born & Wolf, Principles of Optics, 9th Ed. p. 74) stack of 1/4 wavelength (for lambda=546 nm) High n / low n materials at n= 2.3 and 1.35

        59.348,2.3,0
        101.11,1.35,0
        59.348,2.3,0
        101.11,1.35,0
        59.348,2.3,0
    		 Example #2: Specify material using {Material} notation on some or all the layers to obtain dispersive calculations. Cut and paste into box #3 below.

        5.348,{Al}
        101.11,1.35,0
        5.348,{Ag}
        101.11,1.35,0
        59.348,2.3,0

    1 incident angle (theta_i): degrees     centre_lambda: (nm)     wavelength sweep range: +/-nm      # of sweep points:     
    2 index of incident material (eg air) n:     k:     

    Enter the thin film stack text information into the box below
    3
    4 index of susbtrate material (eg glass) ns:     ks:     OR   leave the ns,ks fields blank and select a substrate material:   

    Here is another simple example:
    =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
    Example#2: (Born & Wolf, Principles of Optics, 9th Ed. p. 757) Single layer metal film with thickness = 300nm, n=3.5,k=0.1

        300,3.5,0.1
    =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

    Arbitrary reflection on complex material. Calculate the reflected amplitude coefficients and phase shifts for linearly polarized light at an arbitrary polarization azimuth angle, incident at an arbitrary angle on a material of arbitrary real or complex index of refraction. (Assuming incident medium index =1).
    In the inputs below:
    n and k are respectively the real and imaginary values of the index of refraction, theta_i is the incident angle measured from the normal, angular sweep range is the angular range, centered on theta_i, across which luxpop will perform angle calculations, num sweep points is the number of points that will be computed during the sweeping.
    (For the example given below, the default values below will allow the user to locate the approximate Brewster angle for BK7 in the visible.) The source code for this calculation can be found in the "source code" box at the top of this page.

    n: (real)     k: (complex)     theta_i: degrees    
    angular sweep range: degrees      num sweep points: (max 25)        

    Gaussian Beam Propagation

    Perform calculations on Gaussian beam transformation by a lens. Notes: a) for these calculations the beam waists do not necessarily need to be at the focus, b) results for negative focal length lens may be suspect. Positive focal length calculations are valid.
    Parameters:
    d1,d2 (in millimetres): distance from beam waist to lens; w1, w2 (microns): 1/e2 beam radii at the waist; f (millimetres): lens focal length; l (nm): wavelength.

    If you enter d1, w1, f and l, the algorithm will return d2 and w2; additionally, the algorithm will return wL, the 1/e2 beam radius (although wL is not at a waist) at the lens.

    Additional "sweeping" feature: if one sweep value is entered, Luxpop will perform 15 calculations within a range bounded by the sweep parameter.

    ModeMatching_GaussianBeam.gif (3034 bytes)

                     d1: mm   w1: mm            f:  mm       l: nm            
          sweep:    mm        mm               mm          nm

    Return the Rayleigh range and far field divergence angle given an initial 1/e2 beam radius  at the waist , wo (mm), and a wavelength, l (nm).

    wo: mm        l:nm   

    Return the 1/e2 beam radius  (in mm) given a distance from the waist , z (mm), a beam radius at the waist, wo (mm), and a wavelength l (nm). Additional "sweeping" feature: if one sweep value is entered, Luxpop will perform 15 calculations within a range bounded by the sweep parameter.

    z:   mm     sweep: mm about nominal values
    wo:mm     sweep: mm about nominal values
    l:   nm     sweep: nm about nominal values       

    Conversions

    Convert between photon energy (in eV) , wavelength (nm in vacuum), frequency (Hz), and wavenumber (cm-1).
    If you enter a value in the energy field and leave the others blank, the algorithm will return the wavelength, frequency, and wave number for the given energy.
    If you enter a value in the wavelength field and leave the others blank, the algorithm will return the energy, frequency, and wave number for the given wavelength.
    If you enter a value in the frequency field and leave the others blank, the algorithm will return the wavelength, energy, and wave number for the given frequency.
    If you enter a value in the wave number field and leave the others blank, the algorithm will return the wavelength, frequency, and photon energy for the given wave number.

    Scientific notation is acceptable. Example: entering 192.2e12 for the frequency will properly be interpreted to mean 192.2 THz.

    Photon energy: eV           wavelength: nm                frequency: Hz                wave number: cm-1              

    Return the differential frequency or wavelength  (in GHz or nm) for a given differential wavelength or frequency, centered at the given wavelength.
    If dl is entered and df is left blank, then the differential frequency will be computed.
    If df is entered and dl is left blank, then the differential wavelength will be computed.

     dl: nm    df: GHz     l: nm 

    Convert complex index of refraction to complex permittivity   or vice versa.
    If you enter a value in the n,k fields and leave the permittivities blank, the algorithm will return the permittivities for the given complex index.
    If you enter a value in the e1, e2 fields and leave the indices blank, the algorithm will return the indices  for the given complex permittivities.
    Basic formulae: e1=n2-k2   and e2 =2nk.

            n:            k:              e1:               e2:                        

    Return the finesse for a resonator with the given refractive index, thickness, and reflectivity.

    refractive index:      thickness: mm      reflectivity: %  

    Calculate the carbon footprint of a typical calculation performed on this site, taking into estimated account server farm energy consumption, transmission power through an optical fibre, and more.  

    Click here for more optical computing features.
    Index v70