Mn-doping induced ferromagnetism and enhanced superconductivity in Bi_4-x Mn_x O_4 S_3 (0.075 < = x < = 0.15)

Kavli Affiliate: N. C. Yeh |Summary:We demonstrate that Mn-doping in the layered sulfides Bi_4O_4S_3 leads to stable Bi_4-x Mn_x O_4 S_3 compounds that exhibit both long-range ferromagnetism and enhanced superconductivity for 0.075 < = x < = 0.15, with a possible record superconducting transition temperature (T_c) = 15 K among all BiS_2-based superconductors. We conjecture […]


Continue.. Mn-doping induced ferromagnetism and enhanced superconductivity in Bi_4-x Mn_x O_4 S_3 (0.075 < = x < = 0.15)

Ultra-high Q Acoustic Resonance in Superfluid 4He

Kavli Affiliate: Keith Schwab | Summary:We report the measurement of the acoustic quality factor of a gram-scale, kilo-hertz frequency superfluid resonator, detected through the parametric coupling to a superconducting niobium microwave cavity. For temperature between 400mK and 50mK, we observe a $T^-4$ temperature dependence of the quality factor, consistent with a 3-phonon dissipation mechanism. We […]


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Spectroscopic Studies of the Physical Origin of Environmental Aging Effects on Doped Graphene

Kavli Affiliate: N. C. Yeh |Summary:The environmental aging effect of doped graphene is investigated as a function of the organic doping species, humidity, and the number of graphene layers adjacent to the dopant by studies of the Raman spectroscopy, x-ray and ultraviolet photoelectron spectroscopy, scanning electron microscopy, infrared spectroscopy, and electrical transport measurements. It is […]


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Ordering and dimensional crossovers in metallic glasses and liquids

Kavli Affiliate: Julia R. Greer | Summary:The atomic-level structures of liquids and glasses are amorphous, lacking long-range order. We characterize the atomic structures by integrating radial distribution functions (RDF) from molecular dynamics (MD) simulations for several metallic liquids and glasses: Cu46Zr54, Ni80Al20, Ni33.3Zr66.7, and Pd82Si18. Resulting cumulative coordination numbers (CN) show that metallic liquids have […]


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Macroscopic quantum resonators (MAQRO): 2015 Update

Kavli Affiliate: Keith Schwab | Summary:Do the laws of quantum physics still hold for macroscopic objects – this is at the heart of Schrödinger’s cat paradox – or do gravitation or yet unknown effects set a limit for massive particles? What is the fundamental relation between quantum physics and gravity? Ground-based experiments addressing these questions […]


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A Digital-Receiver for the Murchison Widefield Array

Kavli Affiliate: Jacqueline Barton| First 5 Authors: Thiagaraj Prabu, Thiagaraj Prabu, , , | Summary:An FPGA-based digital-receiver has been developed for a low-frequency imaging radio interferometer, the Murchison Widefield Array (MWA). The MWA, located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia, consists of 128 dual-polarized aperture-array elements (tiles) operating between 80 and 300,MHz, […]


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Microbuckling of Fibrin Provides a Mechanism for Cell Mechanosensing

Kavli Affiliate: David A. Tirrell | Summary:Biological cells sense and respond to mechanical forces, but how such a mechanosensing proccess takes place in a nonlinear inhomogeneous fibrous matrix remains unknown. We show that cells in a fibrous matrix induce deformation fields that propagate over a longer range than predicted by linear elasticity. Synthetic, linear elastic […]


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Synaptic polarity of the interneuron circuit controlling C. elegans locomotion

Kavli Affiliate: Paul W. Sternberg | Summary:C. elegans is the only animal for which a detailed neural connectivity diagram has been constructed. However, synaptic polarities in this diagram, and thus, circuit functions are largely unknown. Here, we deciphered the likely polarities of 7 pre-motor neurons implicated in the control of worm’s locomotion, using a combination […]


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Measurement of the electronic thermal conductance channels and heat capacity of graphene at low temperature

Kavli Affiliate: Keith Schwab | Summary:The ability to transport energy is a fundamental property of the two-dimensional Dirac fermions in graphene. Electronic thermal transport in this system is relatively unexplored and is expected to show unique fundamental properties and to play an important role in future applications of graphene, including opto-electronics, plasmonics, and ultra-sensitive bolometry. […]


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A study of fundamental limitations to statistical detection of redshifted HI from the epoch of reionization

Kavli Affiliate: Jacqueline Barton| First 5 Authors: Nithyanandan Thyagarajan, Nithyanandan Thyagarajan, , , | Summary:In this paper we explore for the first time the relative magnitudes of three fundamental sources of uncertainty, namely, foreground contamination, thermal noise and sample variance in detecting the HI power spectrum from the Epoch of Reionization (EoR). We derive limits […]


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