lin_2012 ======== Z\. Lin, X\. Jia, C\. Wang, Z\. Hu, H\. Kang, W\. Quan, X\. Lai, X\. Liu, J\. Chen, B\. Zeng, W\. Chu, J\. Yao, Y\. Cheng and Z\. Xu, "Ionization Suppression of Diatomic Molecules in an Intense Midinfrared Laser Field", Phys\. Rev\. Lett\. 108, 223001 \(2012\) `Source record `__ · :doc:`Catalogue ` · :doc:`Review register ` DOI: `10\.1103/PhysRevLett\.108\.223001 `__ **Source kind:** measurement **Recorded technique:** Ion time\-of\-flight mass spectrometry \(p\. 2\)\: 'wavelength\-tunable midinfrared femtosecond laser pulses are generated by an optical parametric amplifier \(TOPAS\-C, Light Conversion, Inc\.\) pumped by a commercial Ti\:sapphire laser system \(Legend, Coherent, Inc\.\) \.\.\. The pulse energy from the optical parametric amplifier is variable, before focused into the vacuum chamber, by means of an achromatic half\-wave plate followed by a polarizer\. A standard time\-of\-flight mass spectrometer is used to register the ion signal\. By means of a cryopump, the base pressure of the spectrometer is maintained below 10^\-8 mbar\. At the end of the spectrometer, ions are detected with a microchannel plate as a function of flight time\. The ion signal is further amplified, discriminated, and sent to a multihit time digitizer to generate time\-of\-flight mass spectra\. Depending on the laser intensity, the data point in the ion yield plots is obtained by averaging over 10^4 up to 6 x 10^6 laser shots at each intensity'\. The yields are 'Ion signal \[Counts / \(shot Pa\)\]' \(Fig\. 1's axis\)\: counts per shot and per pascal of the gas\. The 2000 nm light\: 'a linearly polarized light at a center wavelength of 2000 nm'; the 800 nm data are 'recorded at a Ti\:sapphire laser wavelength of 800 nm' \(p\. 2\)\. Not stated\: the pulse durations, the focusing, how the intensity was determined, its uncertainty, the gas pressures, whether the molecule and its atom were measured together \(a mixture\) or one after the other, and any correction of the detector's efficiency\. **Materials in structured entries:** N2, O2 **Dataset quantities:** ionization\_yield\_ratio **Contents:** 4 datasets; 0 formulas. Curation notes -------------- PRL 108, 223001 \(5 pp\.\), PDF pages 1\-5 = 223001\-1 to \-5\. Identity checked on PDF p\. 1 on 2026\-10\-01\: 'Ionization Suppression of Diatomic Molecules in an Intense Midinfrared Laser Field', ZhiYang Lin, XinYan Jia, ChuanLiang Wang, ZiLong Hu, HuiPeng Kang, Wei Quan, XuanYang Lai, XiaoJun Liu, Jing Chen, Bin Zeng, Wei Chu, JinPing Yao, Ya Cheng and ZhiZhan Xu \(Wuhan, Shanghai, Chengdu, Beijing\); '\(Received 8 November 2011; published 29 May 2012\)', 'DOI\: 10\.1103/PhysRevLett\.108\.223001'\. WHAT IS MEASURED\. 'the measured ion yields of singly charged O2 versus Xe and N2 versus Ar' \(Fig\. 1, p\. 2\) and 'the ratio of ionization yield of O2 with respect to Xe in Fig\. 2\(a\) and N2 with respect to Ar in Fig\. 2\(b\)' \(p\. 2\)\: the singly charged ions O2\+/Xe\+ and N2\+/Ar\+ \(the axis labels\), at 800 and 2000 nm, against 'Laser intensity \(TW / cm2\)'\. Fig\. 2 is the only place the ratios are given \(no table, no supplement\); the text prints no value of them\. No error bars are drawn\. DETECTION EFFICIENCY \(detection\_correction = "not stated"\)\. The paper does not mention the detector's efficiency or any correction for it \(the full text searched for 'efficien', 'calibr', 'correct'\)\. Fig\. 2\(a\)'s O2\+/Xe\+ is the quotient of the counts per shot and pascal of Fig\. 1\(a\) \(checked, below\), so no factor is applied between the plotted counts and the ratio\. Not printed here, computed from the standard atomic weights\: dividing each yield by an efficiency ~ Z/M^1/2 \(as Guo et al\. 1998 and Dura et al\. 2012, dura\_2012\) would lower O2\+/Xe\+ by \(M\_Xe/M\_O2\)^1/2 = \(131\.29/32\.00\)^1/2 = 2\.03 and N2\+/Ar\+ by \(39\.95/28\.01\)^1/2 = 1\.194\. INTENSITY\. Not stated how it was determined, nor its uncertainty\: the text names intensities only as 'for the same intensities above 5\-6 x 10^13 W/cm2' \(p\. 2\) and 'the theoretical ratio keeps dropping below 4\-5 x 10^13 W/cm2' \(p\. 4\)\. A ratio at one intensity does not depend on the scale, but its trend with intensity and the comparison of the two wavelengths at 'the same intensities' do\. PULSE DURATION\. Not stated, at either wavelength \(the word 'femtosecond' only\)\. POLARISATION\. 2000 nm\: 'a linearly polarized light' \(p\. 2\)\. 800 nm\: not stated; the S\-matrix rate the paper compares with both wavelengths \(Fig\. 3\) is 'in a linearly polarized laser field' \(Eq\. 1, p\. 3\)\. EXTRACTED \(2026\-10\-01\) by tools/extract/lin\_2012\.py from the vector drawing of Fig\. 2 \(p\. 2\), whose docstring describes the reading\: the log axes calibrated from the frames' own ticks \(11 on x, 30 to 400 TW/cm2, 80\.9 pt per decade; 17 on \(a\)'s y, 0\.025 to 1, 73\.5 pt per decade; 19 on \(b\)'s, 0\.1 to 10, 58\.9 pt per decade\), every tick within 0\.028 pt of the fitted scales; the decades are the labels printed on the page, whose glyphs \(paths, not text\) sit at the long ticks and only there \(checked\)\. Markers\: 800 nm the black filled squares, 2000 nm the red filled circles, the legend's excluded; their centres\. 28 \+ 44 points in \(a\), 25 \+ 32 in \(b\)\. Not curated\: Fig\. 1's yields \(counts per shot and pascal, an unknown detection volume and duration; the O2\+/Xe\+ information is Fig\. 2\(a\)'s\), Figs\. 3 and 4 \(calculations\)\. CHECKS \(the script's checks\(\)\)\. \(1\) Fig\. 2\(a\) against Fig\. 1\(a\)\: every one of the 44 points at 2000 nm and 28 at 800 nm has an O2\+ and a Xe\+ marker of Fig\. 1 \(main panel; the 800 nm inset\) at its intensity within 0\.5 %, and their quotient agrees with it within 0\.7 % \(0\.4 % at 800 nm\), save at 800 nm, 110\.5 TW/cm2, where Fig\. 2 has 0\.156 and the inset 0\.133\. Fig\. 2 leaves out Fig\. 1's five lowest 2000 nm intensities \(25 to 34 TW/cm2\) and one \(78 TW/cm2\) without an O2\+ marker, and the inset's three lowest pairs \(23 to 32 TW/cm2\), its highest \(260 TW/cm2\) and a Xe\+ marker without O2\+ \(18 TW/cm2\)\. \(2\) Fig\. 2\(b\) is not so made throughout\: of its 32 intensities at 2000 nm 17 are Fig\. 1\(b\)'s \(within 0\.5 %\), and there the quotient of Fig\. 1\(b\)'s N2\+ and Ar\+ agrees with Fig\. 2\(b\) within 1 % at the nine from 175 TW/cm2 up and at one at 65 TW/cm2, but differs by up to 25 % at the seven from 72 to 163 TW/cm2; at 800 nm 5 of its 25 intensities are the inset's, and none agrees \(up to 45 %\)\. Fig\. 1\(b\)'s quotients scatter more \(2000 nm 1\.016 to 1\.481, median 1\.170, 43 pairs; 800 nm inset 0\.675 to 1\.811, median 0\.933, 44 pairs\) than Fig\. 2\(b\)'s \(2000 nm 1\.005 to 1\.270, median 1\.061; 800 nm 0\.876 to 1\.005, median 0\.934\)\. How Fig\. 2\(b\) was obtained from the measurement is not stated\. \(3\) The text\: 'the ratio of N2\+/Ar\+ keeps almost constant, to be around 1' \(p\. 2\)\: the 57 points span 0\.876 to 1\.270, median 1\.024\. 'The two ratios \[O2\+/Xe\+\] almost coincide at about the lowest intensity used in the experiment' \(p\. 2\)\: at the lowest 800 nm intensity, 36\.8 TW/cm2, the 2000 nm ratio \(interpolated\) is 1\.13 times the 800 nm one; 'above 5\-6 x 10^13 W/cm2, the longer the wavelength, the less pronounced ionization suppression'\: above 60 TW/cm2 the 2000 nm ratio is 1\.41 times the 800 nm one or more\. 'the ratio of 800 nm increases by about 4 times when the laser intensity increases by about 4 times' and 'depends linearly on the laser intensity \(i\.e\., ~ I\)' \(p\. 3\)\: a power law fitted to the 800 nm points has the exponent 0\.960 \(3\.79 times for 4 times the intensity\); the 2000 nm exponent is 1\.23\. \(4\) The extracted points drawn on the rendered page and inspected on 2026\-10\-01\: every marker of the four series captured once, the legends' markers excluded\. **Recorded bibliographic identity status:** VALIDATED. This concerns identification of the source; it does not establish the scientific correctness of its contents. Datasets -------- lin\_2012/fig2a\_O2\_Xe\_800nm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. code-block:: text { "id": "fig2a_O2_Xe_800nm", "material": "O2", "file": "O2/lin_2012__fig2a_O2_Xe_800nm.csv", "table": "fig_31c497b1a2f7", "digitised": "vector", "quantity": "ionization_yield_ratio", "unit": "1", "abscissa": "intensity", "abscissa_unit": "W/cm2", "use": "check", "uncertainty": { "relative": 0.001, "level": "not stated" }, "parameters": { "companion": "Xe", "wavelength_nm": 800, "polarization": "not stated", "polarization_note": "stated as linear for 2000 nm only ('a linearly polarized light at a center wavelength of 2000 nm', p. 2); the paper's S-matrix rate, compared with both wavelengths, is for linear polarisation", "detection_correction": "not stated", "detection_correction_note": "no efficiency correction mentioned; the ratio is the quotient of Fig. 1's counts per shot and pascal (checked for O2+/Xe+)", "intensity_calibration": "not stated; no uncertainty stated", "pulse_fs_note": "not stated (Ti:sapphire, Coherent Legend)", "mixture": "not stated" } } Fig\. 2\(a\), p\. 2, '800 nm' \(black filled squares\)\: the O2\+/Xe\+ ratio of singly charged ion yields against the intensity, 28 points, 3\.68e13\-2\.40e14 W/cm2, ratio 0\.0707\-0\.354, read from the vector drawing; the quotient of Fig\. 1\(a\)'s inset yields within 0\.4 % \(save 110\.5 TW/cm2\: 0\.156 here, 0\.133 there; the record's notes\)\. No error bars, no uncertainty stated\. No detector\-efficiency correction stated \(with Z/M^1/2 it would be 2\.03 times lower\)\. Intensity\: how determined and its uncertainty not stated\. The text\: 'increases by about 4 times when the laser intensity increases by about 4 times' \(a power law fitted\: exponent 0\.960\)\. 0\.1 %\: the digitising \(the ticks within 0\.03 pt of the scale, 73\.5 pt per decade\); the intensity to 0\.09 %\. lin\_2012/fig2a\_O2\_Xe\_2000nm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. code-block:: text { "id": "fig2a_O2_Xe_2000nm", "material": "O2", "file": "O2/lin_2012__fig2a_O2_Xe_2000nm.csv", "table": "fig_31c497b1a2f7", "digitised": "vector", "quantity": "ionization_yield_ratio", "unit": "1", "abscissa": "intensity", "abscissa_unit": "W/cm2", "use": "check", "uncertainty": { "relative": 0.001, "level": "not stated" }, "parameters": { "companion": "Xe", "wavelength_nm": 2000, "polarization": "linear", "polarization_note": "'a linearly polarized light at a center wavelength of 2000 nm' (p. 2)", "detection_correction": "not stated", "detection_correction_note": "no efficiency correction mentioned; the ratio is the quotient of Fig. 1's counts per shot and pascal (checked for O2+/Xe+)", "intensity_calibration": "not stated; no uncertainty stated", "pulse_fs_note": "not stated (OPA, Light Conversion TOPAS-C)", "mixture": "not stated" } } Fig\. 2\(a\), p\. 2, '2000 nm' \(red filled circles\)\: the O2\+/Xe\+ ratio of singly charged ion yields against the intensity, 44 points, 3\.59e13\-2\.23e14 W/cm2, ratio 0\.0757\-0\.526, read from the vector drawing; the quotient of Fig\. 1\(a\)'s yields within 0\.7 % \(the record's notes\)\. No error bars, no uncertainty stated\. No detector\-efficiency correction stated \(with Z/M^1/2 it would be 2\.03 times lower\)\. Intensity\: how determined and its uncertainty not stated\. The text\: the 800 and 2000 nm ratios 'almost coincide at about the lowest intensity' \(here 1\.13 times the 800 nm one at 36\.8 TW/cm2\) and above 5\-6e13 W/cm2 the 2000 nm one is higher \(1\.41 times or more above 60 TW/cm2\)\. 0\.1 %\: the digitising \(the ticks within 0\.03 pt of the scale, 73\.5 pt per decade\); the intensity to 0\.09 %\. lin\_2012/fig2b\_N2\_Ar\_800nm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. code-block:: text { "id": "fig2b_N2_Ar_800nm", "material": "N2", "file": "N2/lin_2012__fig2b_N2_Ar_800nm.csv", "table": "fig_31c497b1a2f7", "digitised": "vector", "quantity": "ionization_yield_ratio", "unit": "1", "abscissa": "intensity", "abscissa_unit": "W/cm2", "use": "check", "uncertainty": { "relative": 0.0012, "level": "not stated" }, "parameters": { "companion": "Ar", "wavelength_nm": 800, "polarization": "not stated", "polarization_note": "stated as linear for 2000 nm only ('a linearly polarized light at a center wavelength of 2000 nm', p. 2); the paper's S-matrix rate, compared with both wavelengths, is for linear polarisation", "detection_correction": "not stated", "detection_correction_note": "no efficiency correction mentioned (Fig. 1's axis: counts per shot and pascal)", "intensity_calibration": "not stated; no uncertainty stated", "pulse_fs_note": "not stated (Ti:sapphire, Coherent Legend)", "mixture": "not stated" } } Fig\. 2\(b\), p\. 2, '800 nm' \(black filled squares\)\: the N2\+/Ar\+ ratio of singly charged ion yields against the intensity, 25 points, 5\.26e13\-2\.19e14 W/cm2, ratio 0\.876\-1\.005, read from the vector drawing\. Not the quotient of Fig\. 1\(b\)'s inset yields, which scatter from 0\.675 to 1\.811 \(median 0\.933, against 0\.934 here; the record's notes\)\. No error bars, no uncertainty stated\. No detector\-efficiency correction stated \(with Z/M^1/2 it would be 1\.194 times lower\)\. Intensity\: how determined and its uncertainty not stated\. The text\: 'keeps almost constant, to be around 1'\. 0\.12 %\: the digitising \(the ticks within 0\.03 pt of the scale, 58\.9 pt per decade\); the intensity to 0\.09 %\. lin\_2012/fig2b\_N2\_Ar\_2000nm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. code-block:: text { "id": "fig2b_N2_Ar_2000nm", "material": "N2", "file": "N2/lin_2012__fig2b_N2_Ar_2000nm.csv", "table": "fig_31c497b1a2f7", "digitised": "vector", "quantity": "ionization_yield_ratio", "unit": "1", "abscissa": "intensity", "abscissa_unit": "W/cm2", "use": "check", "uncertainty": { "relative": 0.0012, "level": "not stated" }, "parameters": { "companion": "Ar", "wavelength_nm": 2000, "polarization": "linear", "polarization_note": "'a linearly polarized light at a center wavelength of 2000 nm' (p. 2)", "detection_correction": "not stated", "detection_correction_note": "no efficiency correction mentioned (Fig. 1's axis: counts per shot and pascal)", "intensity_calibration": "not stated; no uncertainty stated", "pulse_fs_note": "not stated (OPA, Light Conversion TOPAS-C)", "mixture": "not stated" } } Fig\. 2\(b\), p\. 2, '2000 nm' \(red filled circles\)\: the N2\+/Ar\+ ratio of singly charged ion yields against the intensity, 32 points, 5\.48e13\-2\.20e14 W/cm2, ratio 1\.005\-1\.270, read from the vector drawing\. Not the quotient of Fig\. 1\(b\)'s yields, which scatter from 1\.016 to 1\.481 \(median 1\.170, against 1\.061 here; the record's notes\)\. No error bars, no uncertainty stated\. No detector\-efficiency correction stated \(with Z/M^1/2 it would be 1\.194 times lower\)\. Intensity\: how determined and its uncertainty not stated\. The text\: 'keeps almost constant, to be around 1'\. 0\.12 %\: the digitising \(the ticks within 0\.03 pt of the scale, 58\.9 pt per decade\); the intensity to 0\.09 %\. 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 ` for the checks and decisions.