OPT–PROP

Summary

Defines optical properties of specified materials. ​​

​

See also OPT–PROD, Generating and propagating optical photons, and examples in Handling optical photons

For SDUM = WV–LIMIT: defines wavelength​ range for optical photon transport

WHAT(1) > 0.0:

minimum wavelength​ (in cm) for optical photon transport

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(2.5\times 10^{-5}\)  (250 nm)

WHAT(2) > 0.0:

central wavelength​ (in cm) for optical photon transport

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(5.89\times 10^{-5}\)  (589 nm, Na D line)

WHAT(3) > 0.0:

maximum wavelength​ (in cm) for optical photon transport

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(6.0\times 10^{-5}\)  (600 nm)

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= WV–LIMIT

For SDUM = OM–LIMIT: defines angular frequency​ range for optical photon transport

WHAT(1) > 0.0:

minimum angular frequency​ for optical photon transport \(\omega = 2\pi\nu\) in rad/s

(\(\nu =\) frequency)

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(3.14\times 10^{15}\)  rad/s (corresponding to 600 nm)

WHAT(2) > 0.0:

central angular frequency​ for optical photon transport \(\omega = 2\pi\nu\) in rad/s

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(3.20\times 10^{15}\)  rad/s (corresponding to 589 nm, Na D line)

WHAT(3) > 0.0:

maximum angular frequency​ for optical photon transport \(\omega = 2\pi\nu\) in rad/s

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(7.53\times 10^{15}\)  rad/s (corresponding to 250 nm)

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= OM–LIMIT

For SDUM = RESET: all material optical properties are zeroed

WHAT(1)

– WHAT(3): no meaning

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= RESET

For SDUM = METAL: flag the material as a metal

WHAT(1) =

1\(^{st}\) optical property (not used at the moment)

WHAT(2) =

2\(^{nd}\) optical property (not used at the moment)

WHAT(3) =

3\(^{rd}\) optical property: \((1-r)\), where \(r\) is the reflectivity index​ at the central wavelength (or at the central angular frequency, depending on which one of the two quantities has been defined). See also Note 2

Default

= 0.0

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= METAL

For SDUM = blank:

WHAT(1) =

1\(^{st}\) optical property: refraction index​ \(n_{refr}\) at the central wavelength (or at the central angular frequency, depending on which one of the two quantities has been defined)

< -99:

forces to use user routine RFRNDX (see Note 1)​

Default

= 1.0

WHAT(2) =

2\(^{nd}\) optical property: absorption coefficient​ \(\mu_{abs}\) (in cm\(^{-1}\)) at the central wavelength (or at the central angular frequency, depending on which one of the two quantities has been defined)

< -99:

forces to use a user routine ABSCFF (see Note 1)​

Default

= 0.0

WHAT(3) =

3\(^{rd}\) optical property: diffusion coefficient​ \(\mu_{diff}\) (in cm\(^{-1}\)) at the central wavelength (or at the central angular frequency, depending on which one of the two quantities has been defined)

< -99:

forces to use a user routine DFFCFF (see Note 1)​

Default

= 0.0

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= blank

For SDUM containing “ &1 ” (resp. “ &2 ”) (resp. “ &3 ”):

WHAT(1) =

4\(^{th}\) (resp. 7\(^{th}\)) (resp. 10\(^{th}\)) optical property of the material (derivatives of the refraction index​, see Note 2)

Default

= 0.0

WHAT(2) =

5\(^{th}\) (resp. 8\(^{th}\)) (resp. 11\(^{th}\)) optical property of the material (derivatives of the absorption coefficient​, see Note 2)

Default

= 0.0

WHAT(3) =

6\(^{th}\) (resp. 9\(^{th}\)) (resp. 12\(^{th}\)) optical property of the material (derivatives of the diffusion coefficient​, see Note 2)

WHAT(4)

– WHAT(6): assignment to materials, see below

SDUM

= &1, &2 or &3 in any position in column 71 to 78 (or in the last field if free format is used)

For all previous SDUMs:

WHAT(4) =

lower bound of the indices of materials to which the indicated optical properties refer

(“From material ``WHAT(4)``…”)

Default

= 3.0

WHAT(5) =

upper bound of the indices of materials to which the indicated optical properties refer

(“…to material ``WHAT(5)``…”)

Default

= WHAT(4)

WHAT(6) =

step length in assigning indices

(“…in steps of ``WHAT(6)`` ”)

Default

= 1.0

For SDUM = SENSITIV: sets up the optical photon detection sensitivity​ parameters

(See also SDUM = WV–SENSI, SDUM = OM–SENSI, Note 3 and the examples in Handling optical photons)

WHAT(1) =

0\(^{th}\) optical photon sensitivity​ parameter

< -99:

forces to use user routine QUEFFC (see Note 1)​

WHAT(2) =

1\(^{st}\) optical photon sensitivity parameter

WHAT(3) =

2\(^{nd}\) optical photon sensitivity parameter

WHAT(4) =

3\(^{rd}\) optical photon sensitivity parameter

WHAT(5) =

maximum optical photon sensitivity over the allowed range (must be consistent with the previous values). It can be overestimated.

Default

= 1.0

WHAT(6) =

not used

SDUM

= SENSITIV

For SDUM = WV–SENSI: sets up the wavelength of the optical photon sensitivity

(See also SDUM = SENSITIV, SDUM = OM–SENSI and Note 3.)

WHAT(1) > 0.0:

minimum wavelength (in cm) for optical photon sensitivity

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(2.5\times 10^{-5}\)  (250 nm)

WHAT(2) > 0.0:

central wavelength (in cm) for optical photon sensitivity

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(5.89\times 10^{-5}\)  (589 nm, Na D line)

WHAT(3) > 0.0:

maximum wavelength (in cm) for optical photon sensitivity

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(6.0\times 10^{-5}\)  (600 nm)

WHAT(4)

– WHAT(6): not used

SDUM

= WV–SENSI

For SDUM = OM–SENSI: sets up the angular frequency of the optical photon sensitivity

(See also SDUM = SENSITIV, SDUM = WV–SENSI and Note 3.)

WHAT(1) > 0.0:

minimum angular frequency for optical photon sensitivity \(\omega = 2\pi\nu\) in rad/s

(\(\nu =\) frequency)

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(3.14\times 10^{15}\)  rad/s (corresponding to 600 nm)

WHAT(2) > 0.0:

central angular frequency for optical photon sensitivity \(\omega = 2\pi\nu\) in rad/s

= 0.0:

ignored

< 0.0:

resets to default

Default

= \(3.20\times 10^{15}\)  rad/s (corresponding to 589 nm, Na D line)

WHAT(3) > 0.0:

maximum angular frequency for optical photon sensitivity \(\omega = 2\pi\nu\) in rad/s

Default

= \(7.53\times 10^{15}\)  rad/s (corresponding to 250 nm)

WHAT(4)

– WHAT(6): not used

SDUM

= OM–SENSI

For SDUM = SPEC–BDX: flags special boundary crossings​ for optical photons

At the selected boundary crossings special user-defined properties are defined by means of the user routine OPHBDX​ (see Note 1).

A maximum of 40 boundaries can be flagged by issuing option OPT–PROP with SDUM = SPEC–BDX as many times as needed.

WHAT(1) ≥ 1.0:

special boundary treatment activated for the n\(_{th}\)+1 boundary

= 0.0:

ignored

≤ -1.0:

special boundary treatment deactivated for the n\(_{th}\)+1 boundary

WHAT(2) =

one of the two regions defining the n\(_{th}\)+1 boundary

WHAT(3) =

the other region defining the n\(_{th}\)+1 boundary

WHAT(4) ≥ 1.0:

special boundary treatment activated for the n\(_{th}\)+2 boundary

= 0.0:

ignored

≤ -1.0:

special boundary treatment deactivated for the n\(_{th}\)+2 boundary

WHAT(5) =

one of the two regions defining the n\(_{th}\)+2 boundary

WHAT(6) =

the other region defining the n\(_{th}\)+2 boundary

SDUM

= SPEC–BDX

Default

: (option OPT–PROP not given): no optical photon transport

Notes

1. The optional user routines concerning optical photons are:

   1. RFRNDX:​ to specify a refraction index​ as a function of wavelength, frequency or energy. Activated by setting WHAT(1) < -99 when SDUM = blank.

   2. ABSCFF:​ to specify an absorption coefficient​ as a function of wavelength, frequency or energy. This is activated by setting WHAT(2) < -99 when SDUM = blank.

   3. DFFCFF:​ to specify a diffusion coefficient​ as a function of wavelength, frequency or energy. Activated by setting WHAT(3) < -99 when SDUM = blank.

   4. RFLCTV:​ to specify the reflectivity​ of a material. This can be activated with SDUM = METAL and WHAT(3) < -99

   5. OPHBDX:​ to set optical properties of a boundary surface​. The call is activated with SDUM = SPEC–BDX

   6. FRGHNS:​ to set a possible degree of surface roughness​, in order to have both diffusive​ and specular reflectivity​ from a given material surface

   7. QUEFFC:​ to introduce Quantum Efficiency​. This is activated by setting the 0\(^{th}\) photon sensitivity parameter to a value < -99 with SDUM = SENSITIV.

2. The 9 material properties input by the user with SDUM = &1, &2 and &3 are derivatives of order 1 to 3 of the three basic quantities which are input with SDUM = blank or SDUM = METAL. The three basic quantities and their derivatives are used to perform three series expansions​ centred on the selected central wavelength (if SDUM = WV–LIMIT has been used for the material concerned) or on the selected central angular frequency (if SDUM = OM–LIMIT has been used). The variable \(x\) used in the expansion is adimensional:

   \[x = \frac{\lambda - \lambda_{central}}{\lambda_{central}} {or} x = \frac{\omega - \omega_{central}}{\omega_{central}}\]

   The three basic quantities are:

   If ``SDUM =`` *blank*:

   1. refraction index \(n_{refr}\)

   2. absorption coefficient \(\mu_{abs}\)

   3. diffusion coefficient \(\mu_{diff}\)

   If ``SDUM = METAL``:

   1. (not implemented yet)

   2. (not implemented yet)

   3. \((1-r)\) (\(r\) = reflectivity index)

   The	4\(^{th}\),	5\(^{th}\),	6\(^{th}\) material properties are:	\({ \frac{\mathrm{d} n_{refr}}{\mathrm{d} x}}\),	\({ \frac{\mathrm{d} \mu_{abs}}{\mathrm{d} x}}\),	\({ \frac{\mathrm{d} \mu_{diff}}{\mathrm{d} x} }\)
   the	7\(^{th}\),	8\(^{th}\),	9\(^{th}\) material properties are:	\({ \frac{\mathrm{d}^2 n_{refr}}{\mathrm{d} x^2}}\),	\({ \frac{\mathrm{d}^2 \mu_{abs}}{\mathrm{d} x^2}}\),	\({ \frac{\mathrm{d}^2 \mu_{diff}}{\mathrm{d} x^2} }\)
   the	10\(^{th}\),	11\(^{th}\),	12\(^{th}\) material properties are:	\({ \frac{\mathrm{d}^3 n_{refr}}{\mathrm{d} x^3}}\),	\({ \frac{\mathrm{d}^3 \mu_{abs}}{\mathrm{d} x^3}}\),	\({ \frac{\mathrm{d}^3 \mu_{diff}}{\mathrm{d} x^3} }\)

3. SDUM = SENSITIV can be used to set the quantum efficiency​ as a function of photon energy overall through the problem and it is not material/region dependent. The reason is that it is applied “a priori” at photon generation time. If a quantum efficiency curve is to be introduced at detection, then a weighting user routine should be used, such as FLUSCW​ or COMSCW​. It is advantageous to reduce computer time avoiding to generate and transport a photon which would have a significant probability to remain undetected.

   The optical photon sensitivity parameters are: \(\epsilon(0)\), \(\frac{\mathrm{d}\,\epsilon}{\mathrm{d}\,x}\), \(\frac{\mathrm{d}^2\,\epsilon}{\mathrm{d}\,x^2}\), \(\frac{\mathrm{d}^3\,\epsilon}{\mathrm{d}\,x^3}\) where \(x\) is:

   \[x = \frac{\lambda - \lambda_{central}}{\lambda_{central}} {or} x = \frac{\omega - \omega_{central}}{\omega_{central}}\]

Example 1:

* Optical photon transport requested between 3.E15 and 7.E15 rad/s
* (4.77E5 and 1.11E6 GHz, or 314 to 628 nm) for materials 6,9,12,15 and 18
*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...
OPT-PROP       3.E15     6.E15     7.E15       6.0      18.0       3. OM-LIMIT
* User routine USRMED called when an optical photon is going to be transported
* in materials 6, 12 and 18
MAT-PROP         1.0       0.0       0.0       6.0      18.0       6. USERDIRE

Example 2:
* Material 11 has a reflectivity index = 0.32
*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...
OPT-PROP         0.0       0.0      0.32      11.0       0.0       0. METAL

Example 3:

*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...
* Optical photon transport requested between 300 and 600 nm for water.
* (material 9). The optical properties are for the Na D line (589 nm)
MATERIAL         1.0       0.0  .0000899       3.0       0.0       1. HYDROGEN
MATERIAL         8.0       0.0   0.00143       5.0       0.0       0. OXYGEN
MATERIAL         0.0       0.0       1.0      21.0       0.0       0. WATER
COMPOUND         2.0       3.0       1.0       5.0       0.0       0. WATER
OPT-PROP       3.E-5   5.89E-5     6.E-5      21.0       0.0       0. WV-LIMIT
* diffusion coefficient of water from Appl.Opt. 17, 3587 (1978)
OPT-PROP     1.33299    0.0013   1.22E-5      21.0       0.0       0.