belli_2015#
F. Belli, A. Abdolvand, W. Chang, J. C. Travers and P. St.J. Russell, “Vacuum-ultraviolet to infrared supercontinuum in hydrogen-filled photonic crystal fiber”, Optica 2, 292 (2015)
Source record · Catalogue · Review register
Source kind: theory
Recorded technique: Supercontinuum generation (124 nm to beyond 1200 nm) by 30 fs, 805 nm, few-microjoule pulses in 15 or 25 cm of kagome-style hollow-core photonic crystal fibre (core 25 um) filled with H2 (5 bar), Ar (4 bar) or D2 (5 bar), spectra from three spectrometers (figures only); modelled with a multimode unidirectional field equation whose nonlinear polarisation is an instantaneous Kerr term, a two-level Maxwell-Bloch Raman term for the rotational S(1) and vibrational Q(1) branches of ortho-H2, and PPT photoionisation (pp. 294-297).
Materials in structured entries: H2
Dataset quantities: dephasing_time
Contents: 2 datasets; 2 formulas.
Curation notes#
Journal pages 292-300 = PDF pages 1-9 (page n of the PDF is p. 291 + n). A supercontinuum experiment with simulations: the spectra are figures only (no digitised data). The simulation’s H2 inputs are recorded here; none is a measurement of this paper, and the only quantity that fits one of them as printed is the dephasing time (the rough property values of p. 294, and the model’s formulas below).
MODEL INPUTS WITHOUT A QUANTITY (notes only): - Kerr term, p. 297: ‘P_K = eps0 chi(3) E^3(r, z, t) ... (chi(3) for hydrogen is 2.206 x 10^-26 m^2 V^-2 under standard conditions [42])’, E the real field; [42] = Mizrahi and Shelton, Phys. Rev. A 32, 3454 (1985) (curated as mizrahi_1985_h2d2; how 2.206e-26 follows from it is not said). The convention P = eps0 chi(3) E^3 (real field, SI, per volume) is not among the vocabulary’s third-order conventions, so no nonlinear_susceptibility dataset: a second curator’s decision. For orientation (computed 2026-09-26, not a printed value): with gamma_T = 6 eps0 chi(3)/N it is 699.5 au for N = 2.6868e25 m^-3 (0 C, 1 atm), 750.8 au at 20 C, 1 atm. - Raman shifts, p. 294: ‘Omega_rot/2 pi = 17.6 THz [pure rotational transition, S(1)] and Omega_vib/2 pi = 124.56 THz [pure vibrational transition, Q(1)] for ortho-hydrogen’ (page image checked: the extraction’s ‘17.ar{6}’ is 17.6). raman_shift takes cm^-1 only; not converted. The rotational period is given as 56 fs and the vibrational as 8 fs (pp. 296, 298). - Raman gain, p. 294: ‘a large high-pressure Raman gain coefficient (e.g., 1.55 cm/GW for vibrational mode [18])’, [18] = M. J. Weber, CRC Handbook of Laser Science and Technology Supplement 2 (1994). No quantity. - Two-level polarizability matrix elements, p. 297: (alpha11, alpha22, alpha12, alpha21) = (8.9, 9.4, 0.85, 0.85) x 10^-41 F m^2 for rotation and (8.9, 9.73, 1.55, 1.55) x 10^-41 F m^2 for vibration, orientation-averaged, ‘smaller than those reported in [44,45], but have been carefully checked against ab initio calculations and experimental data’. Model elements (alpha11 is 5.40 au, near H2’s mean polarizability), not a polarizability or a derivative as the vocabulary defines them. - Level lifetimes T1 ‘taken to be ~20 ns in both cases’ (p. 297); rotational revival ~250 fs (H2) and ~500 fs (D2), (2cB)^-1 (p. 296). - Ionisation potentials 15.43 eV (H2) and 15.76 eV (Ar) (pp. 294-295), used in the PPT rate; neither adiabatic nor vertical is said, so no ionization_energy dataset. - Linear index: n_gas ‘obtained from a Sellmeier expansion [22]’, Peck and Huang, J. Opt. Soc. Am. 67, 1550 (1977) (curated as peck_1977), in the capillary model Eq. (1), n_nm = [n_gas^2 - (u_nm lambda/(2 pi a))^2]^(1/2) (Marcatili and Schmeltzer). No values.
Results in the text (figures otherwise): the zero-dispersion wavelength is 446 nm for 5 bar H2 and 4 bar Ar (p. 295), the dispersive wave at 182 nm (H2) and 195 nm (Ar) (p. 295), third harmonic at 268.3 nm near the sixth vibrational anti-Stokes band at 267.7 nm (p. 298), about 5 % conversion into the VUV (p. 299). Not optical constants.
Recorded bibliographic identity status: VALIDATED. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
belli_2015/dephasing_vibrational#
{
"id": "dephasing_vibrational",
"material": "H2",
"table": "text",
"quantity": "dephasing_time",
"unit": "ns",
"abscissa": "pressure",
"abscissa_unit": "bar",
"use": "check",
"parameters": {
"transition": "vibrational (the model's Q(1) of ortho-H2)"
}
}
1 inline points in the source record.
p. 294: ‘a long dephasing time T2 of its molecular oscillations (1 ns and 3 ns, respectively, for vibrational and rotational modes at 1 bar)’; one figure, uncited, room temperature implied. The model’s own T2^(vib) formula (vibrational_T2) gives 0.88 ns at eta = 1.
belli_2015/dephasing_rotational#
{
"id": "dephasing_rotational",
"material": "H2",
"table": "text",
"quantity": "dephasing_time",
"unit": "ns",
"abscissa": "pressure",
"abscissa_unit": "bar",
"use": "check",
"parameters": {
"transition": "rotational (the model's S(1) of ortho-H2)"
}
}
1 inline points in the source record.
p. 294: ‘a long dephasing time T2 of its molecular oscillations (1 ns and 3 ns, respectively, for vibrational and rotational modes at 1 bar)’; one figure, uncited. The model’s own T2^(rot) formula (rotational_T2) gives 2.65 ns at eta = 1.
Formulas#
belli_2015/vibrational_T2#
{
"id": "vibrational_T2",
"material": "H2",
"equation": "text, p. 297",
"printed": "T2^(vib) = 318.3/(309/eta + 52 eta) ns",
"variable": "eta = N_g/N_g0, N_g0 the number density 'in standard conditions'",
"state": "standard conditions (not defined further)",
"density": "unknown",
"range": "not stated",
"coefficients": {
"numerator_ns": "318.3",
"A": "309",
"B": "52"
},
"check": "Reproduces Bischel and Dyer's Q(1) linewidth at 298 K (the cited [35], curated as bischel_1986): their Eq. (1) FWHM = A/rho + B rho with Table I's A = 309 +- 11 MHz amagat, B = 52.2 +- 0.5 MHz/amagat (Eq. (2): 51.8 at 298 K), and T2 = 1/(pi FWHM) = 318.3/FWHM[MHz] ns; 52 is B rounded. At eta = 1, 0.882 ns (checked 2026-09-26)."
}
Reproduced from W. K. Bischel and M. J. Dyer, Phys. Rev. A 33, 3113 (1986) [35] (curated as bischel_1986): a model input (assumed), not this paper’s result. Bischel and Dyer fit 77-500 K, 1-50 amagat, ortho:para 3:1; eta is used as the density in amagat.
belli_2015/rotational_T2#
{
"id": "rotational_T2",
"material": "H2",
"equation": "text, p. 297",
"printed": "T2^(rot) = 318.3/(6.15/eta + 114 eta) ns",
"variable": "eta = N_g/N_g0, N_g0 the number density 'in standard conditions'",
"state": "standard conditions (not defined further)",
"density": "unknown",
"range": "not stated",
"coefficients": {
"numerator_ns": "318.3",
"A": "6.15",
"B": "114"
},
"check": "Not reproduced: cited to Bischel and Dyer [35], whose tables hold only Q-branch linewidths; their Fig. 4 shows the S(1) broadening coefficient (from van den Hout et al., their ref. 10) as a curve near 105 MHz/amagat at 300 K, against 114 here. At eta = 1, 2.65 ns (the text's '3 ns')."
}
A model input (assumed), attributed to [35]; the S(1) values 6.15 MHz amagat and 114 MHz/amagat are not printed there, so their origin is not established. Found 2026-09-27: they are herring_1986’s 295 K S(1) values, the Dicke coefficient A = 6.15 MHz amagat of its Table IV and the FWHM broadening coefficient 114 +- 5 MHz/amagat of its Table V (datasets herring_1986/table4_A and table5_295K), not Bischel and Dyer’s and not van den Hout et al.’s: van_den_hout_1980 (Table I, 293 K, Keijser et al.’s value) gives 1.17 MHz m3/mol = 52.2 MHz/amagat HWHM = 104.4 FWHM for S0(1), the curve Bischel and Dyer’s Fig. 4 shows.
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 review register for the checks and decisions.