milam_1976
==========

D\. Milam and M\. J\. Weber, "Measurement of nonlinear refractive\-index coefficients using time\-resolved interferometry\: Application to optical materials for high\-power neodymium lasers", J\. Appl\. Phys\. 47, 2497\-2501 \(1976\)

`Source record <https://github.com/LupoLab/optmat/blob/main/src/optmat/data/sources/milam_1976.toml>`__ · :doc:`Catalogue </the-data/sources>` · :doc:`Review register </register>`

DOI: `10\.1063/1\.322965 <https://doi.org/10.1063/1.322965>`__

**Source kind:** measurement

**Recorded technique:** Absolute time\-resolved interferometry at 1064 nm \(Sec\. II, pp\. 2497\-2499\)\: linearly polarized ~125\-ps FWHM pulses from a Nd\:YAG oscillator with Nd\:YAG and Nd\:glass amplifiers, up to 25 GW/cm2 at the interferometer, approximately Gaussian in space and time, 1/e2 diameters 6\-12 mm\. A modified Michelson interferometer \(98 % of the intensity in the sample arm\) passes the beam twice through the sample \(discrete paths for apertures \> 2 cm, otherwise one closing mirror with the two transits delayed in time\); the fringes are imaged onto a streak camera \(10\-ps resolution\)\. gamma from the phase shift m lambda at the incident intensity I0 by Eq\. \(3\), gamma = m lambda / \[I0 T\(1 \+ T^2\)\] \[alpha/\(1 \- exp\(\-alpha L\)\)\], T = 4\(n \+ 1\)^\-2 \(printed so; the single\-surface transmittance is 4n/\(n \+ 1\)^2, as weber\_1978's Eq\. \(16\) prints it\)\. Absolute intensity from calibrated beam photographs \(multiple\-replica, film calibration, calorimeter through an aperture\) and the streak record of the waveform \(Appendix\)\. Samples 10\-25 mm in aperture and \>= 100 mm long \(KDP 56 mm\), absorption at 1064 nm negligible \(Cary 17\: optical density 0\.001 measurable\)\.

**Materials in structured entries:** BK7, ED\-2, FK\-5, FK\-51, FR\-5, KDP, MgF2, SiO2

**Dataset quantities:** nonlinear\_index, nonlinear\_index\_field

**Contents:** 15 datasets; 0 formulas.

Curation notes
--------------

Journal pages 2497\-2501 = pdf pages 2\-6 \(journal page = 2495 \+ pdf page; pdf page 1 is the publisher's download cover\)\. Identity checked against the first page\.

DEFINITIONS \(quoted, p\. 2499\)\. Eq\. \(1\), n = n0 \+ Delta n; 'Delta n is frequently expressed in terms of the time\-averaged optical electric\-field amplitude E as n2 \<E^2\>, where the nonlinear refractive\-index coefficient n2 is in electrostatic units\. A more useful expression in practice is Delta n = gamma I, where the beam intensity I is in units of W/cm^2\.' Eq\. \(2\)\: gamma\(cm^2/W\) = \(4 pi x 10^7/cn\) n2\(esu\), c in cm/s\. gamma is optmat's n2 \(nonlinear\_index, the self coefficient of one linearly polarized beam\); n2 is the esu coefficient \(nonlinear\_index\_field\)\. Table I gives both; gamma is what Eq\. \(3\) measures, so the gamma datasets are primary and the esu ones check\. Check \(computed 2026\-09\-27\)\: Eq\. \(2\) with n = n\_D reproduces every gamma from its n2 to the printed digits \(BK 7 3\.426, FC 5 3\.016, fused silica 2\.731, FK 51 1\.945, ED\-2 3\.772, FR\-5 5\.221, KDP 2\.855 with the e\-ray n\_D; printed 3\.43, 3\.01, 2\.73, 1\.94, 3\.77, 5\.2, 2\.9\)\.

PART \(p\. 2499\)\: 'Self\-focusing of laser beams in solids arises from three mechanisms\: Kerr, electrostrictive, and thermal\. The response times for electrostrictive and thermal self\-focusing, however, are much longer than the 125\-ps pulses used for our experiments\. Therefore, the observed fringe shifts are attributed to the optical Kerr effect', and the fringe shift followed the pulse in time \(Fig\. 4, BK 7\)\. The 125\-ps pulses include the whole nuclear \(Raman\) response, and 'for silicate glasses the dominant contribution \(~80%\) to gamma is electronic in origin' \(Ref\. 14, p\. 2500\)\: part = electronic\_vibrational \(no electrostriction or heating\), as in adair\_1989\.

UNCERTAINTY \(p\. 2500 and Appendix\)\. The \+\- of Table I is the estimate for the average of several measurements\: 'total errors of 20% or larger are possible for a single measurement\. To reduce the experimental uncertainty, several measurements were made of each sample to obtain an averaged result with an estimated accuracy of 10\-15%'; intensities 'within \+\-10%, with approximately 3\-4% systematic error remaining after averaging'; fringe shifts 0\.2 \<= m \<= 0\.6 'measured reproducibly to within \+\-10%' \(p\. 2501\)\. Level not stated\. The printed \+\- are 10 % of the value except FR\-5 \(19 %\) and KDP \(30 %\)\.

SAMPLES \(p\. 2500\)\: Schott BK 7, Owens\-Illinois ED\-2 and Dynasil 4000 \(measured before by others\), Hoya FC\-5 \(printed 'FC 5' in Table I\), Schott FK 51, Hoya FR\-5, and KH2PO4 grown by Lasermetrics\. The n\_D and Abbe numbers of Table I are printed without a source; they are kept in each file's printed cells and not recorded as indices\. The glass Milam and Weber name Hoya FC\-5 is recorded as the registered FK\-5\: weber\_1978 \(Table 1, reference a = this paper\) and boling\_1978 print the same value as 'FK\-5', and FC\-5 is Hoya's counterpart of Schott FK5 \(grade 'Hoya FC\-5'\)\.

OTHER VALUES\. Footnote 8 \(p\. 2501\)\: 'The smallest index nonlinearity measured thus far is gamma = \(0\.30 \+\- 0\.1\) x 10^\-16 cm^2/W for MgF2 \(10 cm in length\), M\. Weber and D\. Milam \(unpublished\)'\: dataset gamma\_MgF2\_unpublished \(check\)\. FINDING\: weber\_1978 Table 2 gives MgF2 0\.92 \+\- 0\.31 x 10^\-20 m^2/W \(from Milam, Weber and Glass, Appl\. Phys\. Lett\. 31, 822 \(1977\)\), three times this footnote's value; the paper does not say whether the footnote value was later revised\. The intensity\-dependent ellipsometry values \(Ref\. 4, Owyoung, at 694 nm\) 'are larger \.\.\. due to the frequency dispersion of gamma' \(p\. 2500\)\: not tabulated here\.

FIGURES \(not digitised\)\. Figs\. 1\-2\: the apparatus\. Fig\. 3\: streak photographs of the fringes\. Fig\. 4 \(p\. 2499\)\: the incident pulse and the fringe shift against time for BK 7 \(coincident\)\.

REPRODUCTIONS OF THIS PAPER\: weber\_1978 Table 1 \(reference a\: fused silica, BK\-7, FK\-5, FK\-51, ED\-2, FR\-5\) and Table 2 \(reference d\: KH2PO4\), identical values; milam\_1998 \(its reference 17\: fused silica 2\.73\); adair\_1989 Table III \(TRI column, fused SiO2 0\.95\); boling\_1978 Table III \(n2 exper\); ensley\_2019 \(reference l\); adair\_1987 \(through weber\_1978\)\.

**Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets
--------

milam\_1976/gamma\_MgF2\_unpublished
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_MgF2_unpublished",
     "material": "MgF2",
     "table": "text",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "unknown",
       "coefficient": "self",
       "technique": "time-resolved interferometry (not stated for this value)",
       "form": "bulk"
     }
   }

1 inline points in the source record.

Footnote 8 \(p\. 2501\)\: 'The smallest index nonlinearity measured thus far is gamma = \(0\.30 \+\- 0\.1\) x 10^\-16 cm^2/W for MgF2 \(10 cm in length\), M\. Weber and D\. Milam \(unpublished\)\.' Presumably the same TRI method and 1064\-nm, 125\-ps pulses \(not stated\); orientation and polarization not stated\. weber\_1978 Table 2 gives 0\.92 \+\- 0\.31 x 10^\-20 m^2/W for MgF2 from Milam, Weber and Glass 1977\: a factor 3 apart \(source notes\); kept as a check\.

milam\_1976/gamma\_BK7
~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_BK7",
     "material": "BK7",
     "file": "BK7/milam_1976__gamma_BK7.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Schott BK 7"
     }
   }

Table I \(p\. 2499\), 'BK 7' \(Borosilicate\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, a borosilicate crown glass \(Schott BK 7\); n\_D = 1\.517, Abbe number 64 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\.

milam\_1976/n2\_BK7
~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_BK7",
     "material": "BK7",
     "file": "BK7/milam_1976__n2_BK7.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Schott BK 7"
     }
   }

Table I \(p\. 2499\), 'BK 7'\: the same measurement as gamma\_BK7 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_BK7\.

milam\_1976/gamma\_FK\-5
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_FK-5",
     "material": "FK-5",
     "file": "FK-5/milam_1976__gamma_FK-5.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Hoya FC-5"
     }
   }

Table I \(p\. 2499\), 'FC 5' \(Fluorosilicate\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, a fluorosilicate glass \(Hoya FC\-5\); n\_D = 1\.487, Abbe number 70 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\. Printed 'FC 5' \(Hoya FC\-5, 'kindly provided by Hoya Glass Works', p\. 2500\); recorded under the registered FK\-5, the name weber\_1978 and boling\_1978 print for this same value\.

milam\_1976/n2\_FK\-5
~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_FK-5",
     "material": "FK-5",
     "file": "FK-5/milam_1976__n2_FK-5.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Hoya FC-5"
     }
   }

Table I \(p\. 2499\), 'FC 5'\: the same measurement as gamma\_FK\-5 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_FK\-5\.

milam\_1976/gamma\_SiO2
~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_SiO2",
     "material": "SiO2",
     "file": "SiO2/milam_1976__gamma_SiO2.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Dynasil 4000"
     }
   }

Table I \(p\. 2499\), '4000' \(Fused silica\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, fused silica \(Dynasil 4000\); n\_D = 1\.458, Abbe number 68 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\.

milam\_1976/n2\_SiO2
~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_SiO2",
     "material": "SiO2",
     "file": "SiO2/milam_1976__n2_SiO2.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Dynasil 4000"
     }
   }

Table I \(p\. 2499\), '4000'\: the same measurement as gamma\_SiO2 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_SiO2\.

milam\_1976/gamma\_FK\-51
~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_FK-51",
     "material": "FK-51",
     "file": "FK-51/milam_1976__gamma_FK-51.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Schott FK 51"
     }
   }

Table I \(p\. 2499\), 'FK 51' \(Fluorophosphate\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, a fluorophosphate glass \(Schott FK 51\); n\_D = 1\.487, Abbe number 84 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\.

milam\_1976/n2\_FK\-51
~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_FK-51",
     "material": "FK-51",
     "file": "FK-51/milam_1976__n2_FK-51.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Schott FK 51"
     }
   }

Table I \(p\. 2499\), 'FK 51'\: the same measurement as gamma\_FK\-51 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_FK\-51\.

milam\_1976/gamma\_ED\-2
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_ED-2",
     "material": "ED-2",
     "file": "ED-2/milam_1976__gamma_ED-2.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Owens-Illinois ED-2"
     }
   }

Table I \(p\. 2499\), 'ED\-2' \(Nd silicate laser glass\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, a Nd\-silicate laser glass \(Owens\-Illinois ED\-2\); n\_D = 1\.567, Abbe number 54 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\. weber\_1978 prints ED\-2's n\_D as 1\.572\.

milam\_1976/n2\_ED\-2
~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_ED-2",
     "material": "ED-2",
     "file": "ED-2/milam_1976__n2_ED-2.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Owens-Illinois ED-2"
     }
   }

Table I \(p\. 2499\), 'ED\-2'\: the same measurement as gamma\_ED\-2 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_ED\-2\.

milam\_1976/gamma\_FR\-5
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_FR-5",
     "material": "FR-5",
     "file": "FR-5/milam_1976__gamma_FR-5.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Hoya FR-5"
     }
   }

Table I \(p\. 2499\), 'FR\-5' \(Tb silicate Faraday rotator glass\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, a Tb\-silicate Faraday rotator glass \(Hoya FR\-5\); n\_D = 1\.686, Abbe number 52 \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\.

milam\_1976/n2\_FR\-5
~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_FR-5",
     "material": "FR-5",
     "file": "FR-5/milam_1976__n2_FR-5.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Hoya FR-5"
     }
   }

Table I \(p\. 2499\), 'FR\-5'\: the same measurement as gamma\_FR\-5 in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_FR\-5\.

milam\_1976/gamma\_KDP
~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "gamma_KDP",
     "material": "KDP",
     "file": "KDP/milam_1976__gamma_KDP.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index",
     "unit": "cm2/W",
     "scale": 1e-16,
     "abscissa_unit": "nm",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Lasermetrics"
     }
   }

Table I \(p\. 2499\), 'Tetragonal' \(KH2PO4 nonlinear crystal\)\: gamma \(Delta n = gamma I\) in 10^\-16 cm^2/W with its \+\-, KH2PO4 grown by Lasermetrics, 56 mm long; n\_D = 1\.468 \(e\), 1\.509 \(o\), Abbe number 70 \(e\), 57 \(o\) \(printed, source of the indices not stated\)\. An average of several measurements, 'estimated accuracy of 10\-15%' \(p\. 2500\)\. Orientation and polarization relative to the axes not stated; Eq\. \(2\) reproduces gamma from n2 with the e\-ray n\_D \(2\.855, printed 2\.9; with the o ray 2\.778\), so the beam was presumably e\-polarized\. 'The uncertainty of the KDP datum is larger, however, because the fringe shifts were small and only two measurements were made' \(p\. 2500\)\.

milam\_1976/n2\_KDP
~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "n2_KDP",
     "material": "KDP",
     "file": "KDP/milam_1976__n2_KDP.csv",
     "table": "tbl_9e8c390f5b4c",
     "quantity": "nonlinear_index_field",
     "unit": "esu",
     "scale": 1e-13,
     "abscissa_unit": "nm",
     "use": "check",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "definition": "<E^2>, 'the time-averaged optical electric-field amplitude E' (p. 2499)",
       "part": "electronic_vibrational",
       "coefficient": "self",
       "technique": "time-resolved interferometry (double-pass modified Michelson, streak camera)",
       "polarization": "linear",
       "pulse_fs": 125000,
       "form": "bulk",
       "grade": "Lasermetrics"
     }
   }

Table I \(p\. 2499\), 'Tetragonal'\: the same measurement as gamma\_KDP in 10^\-13 esu \(n = n0 \+ n2 \<E^2\>\), related to gamma by Eq\. \(2\) with n = n\_D \(source notes\); a second statement of one measurement, never to be used beside gamma\_KDP\.

Formulas
--------

No formulas are recorded.

Corrections
-----------

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the :doc:`review register </register>` for the checks and decisions.