Using time-differential perturbed angular correlation spectroscopy we have measured the electric field gradient ͑EFG͒ at 111 Cd probe nuclei in solid Ce in a pressure range up to 8 GPa. Covering various allotropic phases of Ce, we find that the value of the EFG in the cubic ␣ phase is almost four times larger than in the cubic ␥ phase and close to values in the noncubic phases ␣Ј and ␣Љ. These results together with the differences in time modulation of the spectra are interpreted as evidence for quadrupolar electronic charge-density ordering and symmetry lowering at the ␥ → ␣ transition while the lattice remains face-centered cubic.

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The time‐differential perturbed angular correlation (TDPAC) of the 133–482 keV γ‐ray cascade in 181Ta in the intermetallic compound Hf2Fe is measured in the temperature range 78 to 903 K. At 78 K the following parameters of the electric field gradient (EFG) at the two unequivalent Hf sites are obtained: V italiczz(1) = (1.91 ± 0.14) × 1022 V/m2, η(1) = 0.505(7); V italiczz(2) = (1.05 ± 0.2) × 1021 V/m2, η(2) = 0 (fixed parameter). Discontinuities in the temperature dependence of the EFG parameters at T ≈︁ 600 K are observed as well as an indication at the possible existence of the third Hf site above 600 K.

Broadband quantum noise suppression of light is required for many applications, including detection of gravitational waves, quantum sensing, and quantum communication. Here, using numerical simulations, we investigate the possibility of polarization squeezing of ultrashort soliton pulses in an optical fiber with an enlarged mode field area, such as large-mode area or multicore fibers (to scale up the pulse energy). Our model includes the second-order dispersion, Kerr and Raman effects, quantum noise, and optical losses. In simulations, we switch on and switch off Raman effects and losses to find their contribution to squeezing of optical pulses with different durations (0.1–1 ps). For longer solitons, the peak power is lower and a longer fiber is required to attain the same squeezing as for shorter solitons, when Raman effects and losses are neglected. In the full model, we demonstrate optimal pulse duration (~0.4 ps) since losses limit squeezing of longer pulses and Raman effects limit squeezing of shorter pulses.

Radioactive 111In was introduced into the Laves phases YMn2, GdFe2 and YbFe2 synthesized under pressure of 8 GPa, and the hyperfine interaction of the daughter 111Cd was measured by the perturbed angular correlation method. In the obtained hexagonal (C14) phase YMn2 111In is substituted for Mn, predominantly at h‐sites, experiencing there an electric quadrupole interaction with νQ = 32.0(5) MHz and η = 0.51(5) at 300 K. In GdFe2 and YbFe2 (cubic C15) most of the 111In–111Cd probes (≈︂80%) substituted mainly for the rare earth atoms and experienced a magnetic hyperfine field |Bhf| = 2.92(4) T and 3.32(7) T, respectively, at 300 K. The results are discussed together with the published data for the normal cubic YMn2, and for LuFe2 and ZrFe2.