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© 2020 IOP Publishing Ltd. The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument able to detect gravitational waves at distances 5 times further away than possible with Advanced LIGO, or at greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby Universe, as well as observing the Universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor.

In this paper, we present the colossal dielectric behavior of T-type La2CuO4-delta (LCO) ceramics synthesized in fine grained form using wet chemical "Pechini" process, followed by annealing in argon (Ar) atmosphere. The colossal dielectric constant (CDC) (10(3)

The magnetic, magneto-transport and magnetocaloric properties of antiferromagnetic intermetallic compound NdCo2Si2 (T-N = 32 K) have been studied. The compound yields a positive magnetoresistance (MR) of about similar to 123% at similar to 5 K in 8 T magnetic field. The MR value is significantly large vis - a - vis earlier reports of large MR in intermetallic compounds, and possibly associated with the changes in magnetic structure of the compound. The large MR value can be explained in terms of field induced pseudo-gaps on Fermi surface. (C) 2017 Elsevier B.V. All rights reserved.

We present the first high resolution vacuum ultraviolet photoabsorption study of amorphous benzene with comparisons to annealed crystalline benzene and the gas phase. Vapour deposited benzene layers were grown at 25 K and annealed to 90 K under conditions pertinent to interstellar icy dust grains and icy planetary bodies in our Solar System. Three singlet-singlet electronic transitions in solid benzene correspond to the 1B2u, 1B1u and 1E1u states, redshifted by 0.05, 0.25 and 0.51 eV respectively with respect to the gas phase. The symmetry forbidden 1B2u←1A1g and 1B1u←1A1g transitions exhibit vibronic structure due to vibronic coupling and intensity borrowing from the allowed 1E1u←1A1g transition. Additionally the 1B2u←1A1g structure shows evidence of coupling between intramolecular vibrational and intermolecular lattice modes in crystalline benzene with Davydov crystal field splitting observed. The optically forbidden 0–0 electronic origin is clearly visible as a doublet at 4.69/4.70 eV in the crystalline solid and as a weak broadened feature at 4.67 eV in amorphous benzene. In the case of the 1B1u←1A1g transition the forbidden 0–0 electronic origin is only observed in crystalline benzene as an exciton peak at 5.77 eV. Thicker amorphous benzene samples show diffuse bands around 4.3, 5.0 and 5.4 eV that we tentatively assign to spin forbidden singlet-triplet 3B2u←1A1g, 3E1u←1A1g and 3B1u←1A1g transitions respectively, not previously reported in photoabsorption spectra of amorphous benzene. Furthermore, our results show clear evidence of non-wetting or ‘islanding’ of amorphous benzene, characterised by thickness-dependent Rayleigh scattering tails at wavelengths greater than 220 nm. These results have significant implications for our understanding of the physical and chemical properties and processes in astrochemical ices and highlight the importance of VUV spectroscopy.

Lithium gets a new ground state For the past 70 years, the lowest-energy crystal structure of lithium was believed to be a relatively complex one called the 9R structure. Ackland et al. show that this is incorrect. The actual lowest-energy structure for lithium is the much simpler closest-packed face-centered cubic form. In addition, 6 Li and 7 Li isotopes have crystal phase transitions at slightly different pressures and temperatures. This difference is chalked up to large quantum mechanical effects between the isotopes. Lithium is the only metal that shows this type of quantum effect and presents a challenge for theoreticians to explain. Science , this issue p. 1254

We report quantum transport measurements on two dimensional (2D) Si:P and Ge:P δ-layers and compare the inelastic scattering rates relevant for weak localization (WL) and universal conductance fluctuations (UCF) for devices of various doping densities (0.3–2.5 × 1018 m−2) at low temperatures (0.3–4.2 K). The phase breaking rate extracted experimentally from measurements of WL correction to conductivity and UCF agree well with each other within the entire temperature range. This establishes that WL and UCF, being the outcome of quantum interference phenomena, are governed by the same dephasing rate.

Current interferometric gravitational wave detectors use the combination of quasi-monochromatic, continuous-wave laser light at 1064 nm and fused silica test masses at room temperature. Detectors of the third generation, such as the Einstein-Telescope, will involve a considerable sensitivity increase. The combination of 1550 nm laser radiation and crystalline silicon test masses at low temperatures might be important ingredients in order to achieve the sensitivity goal. Here we compare some properties of the fused silica and silicon test mass materials relevant for decreasing the thermal noise in future detectors as well as the recent technology achievements in the preparation of laser radiation at 1064 nm and 1550 nm relevant for decreasing the quantum noise. We conclude that silicon test masses and 1550 nm laser light have the potential to form the future building blocks of gravitational wave detection. DFG/EXC/QUEST DFG/SFB/TR7 EC/FP7/2007-2013

We study the Pb growth on both root 3 x root 3-In and 4 x 1-In reconstructed Si(111) surfaces at room and low temperature (160 K). The study takes place with complementary techniques, to investigate the role of the substrate reconstruction and temperature in determining the growth mode of Pb. Specifically, we focus on the correlation between the growth morphology and the electronic structure of the Pb films. The information is obtained by using Auger electron spectroscopy, low energy electron diffraction, soft x-ray photoelectron spectroscopy, scanning tunneling microscopy and spot profile analysis-low energy electron diffraction. The results show that, at low temperature and coverage

Motivated by a number of recent experimental studies we have revisited the problem of the microscopic calculation of the quasiparticle self-energy and many-body effective mass enhancement in a two-dimensional electron liquid. Our systematic study is based on the many-body local fields theory and takes advantage of the results of the most recent Diffusion Monte Carlo calculations of the static charge and spin response of the electron liquid. We report extensive calculations of both the real and imaginary parts of the quasiparticle self-energy. We also present results for the many-body effective mass enhancement and the renormalization constant over an extensive range of electron density. In this respect we critically examine the relative merits of the on-shell approximation versus the self-consistent solution of the Dyson equation. We show that in the strongly-correlated regime a solution of the Dyson equation proves necessary in order to obtain a well behaved effective mass. The inclusion of both charge- and spin-density fluctuations beyond the Random Phase Approximation is indeed crucial to get reasonable agreement with recent measurements., Comment: 41 pages, 16 figures, 1 table, submitted

Self- and argon-broadening coefficients are reported for a number of Raman Q-branch transitions in the nu(1) and nu(2) + nu(4) bands of (C-12)D4 at room temperature (296 K). The coefficients display a variation with j and with C exp n (symmetry species A, E, F) that is essentially independent of collision partner and which is similar to the j- and C exp n-dependence found in previous measurements of the IR line-broadening coefficients. The rotationally inelastic collision rates previously measured by Foy et al. (1988) for (C-13)D4 (V4 = 0, 1) in collision with (C-13)D4 or Ar account for only a part of the Raman broadening rate, suggesting possibly significant contributions to the linewidths from efficient V-V transfer or elastic dephasing collisions.

Doping of silicon via phosphine exposures alternating with molecular beam epitaxy overgrowth is a path to Si:P substrates for conventional microelectronics and quantum information technologies. The technique also provides a new and well-controlled material for systematic studies of two-dimensional lattices with a half-filled band. We show here that for a dense (ns = 2.8 × 1014 cm−2 ) disordered two-dimensional array of P atoms, the full field angle-dependent magnetostransport is remarkably well described by classic weak localization theory with no corrections due to interaction effects. The two- to three-dimensional cross-over seen upon warming can also be interpreted using scaling concepts, developed for anistropic three-dimensional materials, which work remarkably except when the applied fields are nearly parallel to the conducting planes.

We present the optical and mechanical properties of high-Q fused silica microtoroidal resonators at cryogenic temperatures (down to 1.6 K). A thermally induced optical multistability is observed and theoretically described; it serves to characterize quantitatively the static heating induced by light absorption. Moreover the influence of structural defect states in glass on the toroid mechanical properties is observed and the resulting implications of cavity optomechanical systems on the study of mechanical dissipation discussed., 4 pages, 3 figures