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'Sudden' quantum quench and prethermalization have become a cross-cutting theme for discovering emergent states of matter. Yet this remains challenging in electron matter, especially superconductors. The grand question of what is hidden underneath superconductivity (SC) appears universal, but poorly understood. Here we reveal a long-lived gapless quantum phase of prethermalized quasiparticles (QPs) after a single-cycle terahertz (THz) quench of a NbSn SC gap. Its conductivity spectra is characterized by a sharp coherent peak and a vanishing scattering rate that decreases almost linearly towards zero frequency, which is most pronounced around the full depletion of the condensate and absent for a high-frequency pump. Above a critical pump threshold, such a QP phase with coherent transport and memory persists as an unusual prethermalization plateau, without relaxation to normal and SC thermal states for an order of magnitude longer than the QP recombination and thermalization times. Switching to this metastable 'quantum QP fluid' signals non-thermal quench of coupled SC and charge-density-wave (CDW)-like orders and hints quantum control beneath the SC.

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A grand challenge underlies the entire field of topology-enabled quantum logic and information science: how to establish topological control principles driven by quantum coherence and understand the time-dependence of such periodic driving? Here we demonstrate a THz pulse-induced phase transition in Dirac materials that is periodically driven by vibrational coherence due to excitation of the lowest Raman-active mode. Above a critical field threshold, there emerges a longlived metastable phase with unique Raman coherent phonon-assisted switching dynamics, absent for optical pumping. The switching also manifest itself by non-thermal spectral shape, relaxation slowing down near the Lifshitz transition where the critical Dirac point (DP) occurs, and diminishing signals at the same temperature that the Berry curvature induced Anomalous Hall Effect varnishes. These results, together with first-principles modeling, identify a mode-selective Raman coupling that drives the system from strong to weak topological insulators, STI to WTI, with a Dirac semimetal phase established at a critical atomic displacement controlled by the phonon pumping. Harnessing of vibrational coherence can be extended to steer symmetry-breaking transitions, i.e., Dirac to Weyl ones, with implications on THz topological quantum gate and error correction applications.

Marek's disease (MD), caused by the oncogenic MD avian herpes virus (MDV), is a major source of economic losses to the poultry industry. A reciprocal backcross (BC) population (total 2052 individuals) was generated by crossing two partially inbred commercial Leghorn layer lines known to differ in MDV resistance, measured as survival time after challenge with a (vv1) MDV. QTL affecting resistance were identified by selective DNA pooling using a panel of 198 microsatellite markers covering two-thirds of the chicken genome. Data for each BC were analyzed separately, and as a combined data set. Markers showing significant association with resistance generally appeared in blocks of two or three, separated by blocks of nonsignificant markers. Defined this way, 15 chromosomal regions (QTLR) affecting MDV resistance, distributed among 10 chromosomes (GGA 1, 2, 3, 4, 5, 7, 8, 9, 15, and Z), were identified. The identified QTLR include one gene and three QTL associated with resistance in previous studies of other lines, and three additional QTL associated with resistance in previous studies of the present lines. These QTL could be used in marker-assisted selection (MAS) programs for MDV resistance and as a platform for high-resolution mapping and positional cloning of the resistance genes.

Using density matrix equations of motion, we predict a femtosecond collective spin tilt triggered by nonlinear, near-ultraviolet (∼3eV), coherent photoexcitation of (Ga,Mn)As ferromagnetic semiconductors with linearly polarized light. This dynamics results from carrier coherences and nonthermal populations excited in the {111} equivalent directions of the Brillouin zone and triggers a subsequent uniform precession. We predict nonthermal magnetization control by tuning the laser frequency and polarization direction. Our mechanism explains recent ultrafast pump-probe experiments.PACS numbers: 78.47. 78.20.Ls, 78.47.Fg, 42.50.Md Long range magnetic order arises from the interactions between itinerant and localized spins in a wide variety of systems, such as EuO, EuS, chrome spinels, pyrochlore, manganese oxides, or (III,Mn)V ferromagnetic semiconductors [1,2]. With ferromagnetic semiconductors one can envision multifunctional devices combining information processing and storage on a single chip with low power consumption. Fast spin manipulation is of great importance for such spin-electronic, spin-photonic, magnetic storage, and quantum computation applications.One of the challenges facing magnetic devices concerns their speed. The magnetic properties of carrier-induced ferromagnets respond strongly to carrier density tuning via light, electrical gates, or current [3]. While magnetic field pulses and spin currents can be used to manipulate spin on the many-picosecond time scale, femtosecond spin manipulation requires the use of laser pulses [4,5]. In ultrafast pump-probe magneto-optical spectroscopy, the pump optical pulse excites e-h coherences and corresponding carrier populations, whose subsequent interactions trigger a magnetization dynamics monitored as function of time via the Faraday or Kerr rotation [6].The physical processes leading to femtosecond magnetization dynamics (femto-magnetism) are under debate. Open questions include the possibility of direct photonspin coupling, the distinction of coherent and incoherent effects, and the exact role of the spin-orbit interaction. Following the pioneering work of Ref. [7], many ultrafast spectroscopy experiments were interpreted in terms of a decrease in the magnetization amplitude due to transient thermal effects [7,8]. Observations of lightinduced changes in the magnetization orientation were also mostly attributed to the temperature elevation, which leads to transient changes in the magnetic easy axes [9,10,11]. Most desirable is nonthermal magnetization control within the femtosecond coherent [12] temporal regime, which promises more flexibility limited only by the optical pulse duration. Experiments in ferrimagnetic garnets were interpreted in terms of an interplay between the inverse Faraday effect [13] and long-lived changes in the magneto-crystalline anisotropy [4]. In (Ga,Mn)As, Ref.[14] reported magnetization precession triggered by changes of magnetic anisotropy on a ∼100ps time scale due to carrier relaxation, while Ref.[15] demonstrated coherent ...

Proteins are separated by size exclusion chromatography while atomic ions from the inorganic elements are detected on-line by inductively coupled plasma-mass spectrometry. A double focusing mass analyzer provides very high sensitivity, low background, and sufficient spectral resolution to separate the atomic ions of interest from most polyatomic ions at the same nominal m/z value. The chromatograms show the distribution of the elements of interest between protein-bound and free fractions and provide the approximate molecular weights of those protein fractions that contain the elements monitored. The distribution of various elements, including V, Mo, Fe, Co, Mn, and lanthanides, in human or bovine serum samples are shown. Alkali metals and Tl are present primarily as free metal ions and are not bound to proteins. Inorganic elements spiked into the serum samples can be followed into various proteins. EDTA does not remove Fe, Pb, Sn, or Th from the proteins but does extract Mn from some proteins. Procedures for determining the effects of breaking disulfide linkages on the metal binding characteristics of proteins are also described.

We demonstrate an ultrafast reversible modulation of resonant terahertz (THz) response in strongly photoexcited metamaterials. The transient spectral-temporal response of the dipole transition ∼1.6 THz exhibits a distinct non-monotonic variation as a function of pump fluence. The transition energy shift, strength, spectral width, and density-dependent ultrafast relaxation manifest a remarkable re-emergence of the transmission dip after initial quenching. Our simulations, incorporating the first-order diffraction from the photoinduced transient grating, reproduce the salient features, providing a new avenue for designing nonlinear and frequency-agile THz modulators.