A conditional quantum phase gate between two 3-state atoms

We propose a scheme for conditional quantum logic between two 3-state atoms that share a quantum data-bus such as a single mode optical field in cavity QED systems, or a collective vibrational state of trapped ions. Making use of quantum interference, our scheme achieves successful conditional phase evolution without any real transitions of atomic internal states or populating the quantum data-bus. In addition, it only requires common addressing of the two atoms by external laser fields.Comment: 8 fig

Fermi gas in harmonic oscillator potentials

Assuming the validity of grand canonical statistics, we study the properties of a spin-polarized Fermi gas in harmonic traps. Universal forms of Fermi temperature $T_F$, internal energy $U$ and the specific heat per particle of the trapped Fermi gas are calculated as a {\it function} of particle number, and the results compared with those of infinite number particles.Comment: 8 pages, 1 figure, LATE

The Fermi surface of underdoped high-T_c superconducting cuprates

The coexistence of $\pi$-flux state and d-wave RVB state is considered in this paper within the slave boson approach. A critical value of doping concentration $\delta_c$ is found, below which the coexisting $\pi$-flux and d-wave RVB state is favored in energy. The pseudo Fermi surface of spinons and the physical electron spectral function are calculated. A clear Fermi-level crossing is found along the (0,0) to ($\pi$, $\pi$) direction, but no such crossing is detected along the ($\pi$, 0) to ($\pi$, $\pi$) direction. Also, an energy gap of d-wave symmetry appears at the Fermi level in our calculation. The above results are in agreement with the angle-resolved photoemission experiments which indicate at a d-wave pseudo-gap and a half-pocket-like Fermi surface in underdoped cuprates.Comment: 18 pages RevTex, 6 figures in PS file

Immunogenicity of novel sulfadimethoxide conjugates

Sulfadimethoxine (SDM) is an antibiotic commonly added to animal feeds. Anti-SDM antibodies are useful for the detection of residual SDM in foods, feeds and biological fluids by ELISA. In this study, we show that SDM is immunogenic in rabbits when it is conjugated with soy 11S globulin or with β- amylase. Rabbit anti-SDM antibodies obtained by immunization with SDM-11S and SDM-beta-amylase displayed low cross-reactivity against other sulfonamides, including sulfamethazine (SM2), sulfasulfonamides (SN), sulfadiazine (SD), sulfamethoxypyrazine (SMP), sulfalene (SMZ), sulfaquinoxaline (SQX). Thus, soy 11S globulin and β-amylase are suitable carriers for the induction of anti-SDM antibodies and have the advantage of being cheaper that BSA.Key words: Sulfadimethoxine (SDM), sulfasulfonamides (SN), sulfadiazine (SD), sulfamethazine (SM2), sulfamethoxypyrazine (SMP), sulfalene (SMZ), sulfaquinoxaline (SQX), rabbit anti-SDM antibodies, soy 11S globulin, SDM-beta-amylase

Translation-symmetry protected topological orders on lattice

In this paper we systematically study a simple class of translation-symmetry protected topological orders in quantum spin systems using slave-particle approach. The spin systems on square lattice are translation invariant, but may break any other symmetries. We consider topologically ordered ground states that do not spontaneously break any symmetry. Those states can be described by Z2A or Z2B projective symmetry group. We find that the Z2A translation symmetric topological orders can still be divided into 16 sub-classes corresponding to 16 new translation-symmetry protected topological orders. We introduced four $Z_2$ topological indices $\zeta_{\v{k}}=0,1$ at $\v {k}=(0,0)$, $(0,\pi)$, $(\pi, 0)$, $(\pi ,\pi)$ to characterize those 16 new topological orders. We calculated the topological degeneracies and crystal momenta for those 16 topological phases on even-by-even, even-by-odd, odd-by-even, and odd-by-odd lattices, which allows us to physically measure such topological orders. We predict the appearance of gapless fermionic excitations at the quantum phase transitions between those symmetry protected topological orders. Our result can be generalized to any dimensions. We find 256 translation-symmetry protected Z2A topological orders for a system on 3D lattice

Research on evaporation of Taiyuan basin area by using remote sensing

International audienceTaiyuan basin is enclosed by hills and mountains, located in the middle of Shanxi province, standing between longitudes 111°40'?113°00'E and latitude 37°00'?38&deg00'N. With various types and wide distribution, the mineral resources are very abundant in this basin area. However, there is a great shortage of water resources. Due to continual fall of groundwater level caused by excessive extraction of ground water, some severe environmental problems are induced in this area, such as ground subsidence, etc. The goal of this paper is to estimate the spatial distribution of actual evaporation over the basin by using remote sensing data. The Surface Energy Balance System (SEBS) has been developed (Su, 2001, 2002). Using visible and infrared satellite remote sensing data, SEBS is based on land surface energy balance theory combined with the in-situ meteorological data or the product of atmospheric numerical model to estimate land surface turbulent flux and the relative evaporation at different scales. SEBS was served as the core methodology of this paper and was used for evaporation estimation. On the basis of hydro-geological data and NOAA satellite data, the SEBS was used in this paper for the estimation of actual evaporation of Taiyuan basin. The spatial distribution of the evaporative fraction and daily evaporation over the basin area was shown. On the other hand, the difference of land surface parameters and evaporation for various target types in the basin area was discussed

Studies on Temperature and Strain Sensitivities of a Few-mode Critical Wavelength Fiber Optic Sensor

This paper studied the relationship between the temperature/strain wavelength sensitivity of a fiber optic in-line Mach-Zehnder Interferometer (MZI) sensor and the wavelength separation of the measured wavelength to the critical wavelength (CWL) in a CWL-existed interference spectrum formed by interference between LP01 and LP02 modes. The in-line MZI fiber optic sensor has been constructed by splicing a section of specially designed few-mode fiber (FMF), which support LP01 and LP02 modes propagating in the fiber, between two pieces of single mode fiber. The propagation constant difference, Δβ, between the LP01 and LP02 modes, changes non-monotonously with wavelength and reaches a maximum at the CWL. As a result, in sensor operation, peaks on the different sides of the CWL then shift in opposite directions, and the associated temperature/strain sensitivities increase significantly when the measured wavelength points become close to the CWL, from both sides of the CWL. A theoretical analysis carried out has predicted that with this specified FMF sensor approach, the temperature/strain wavelength sensitivities are governed by the wavelength difference between the measured wavelength and the CWL. This conclusion was seen to agree well with the experimental results obtained. Combining the wavelength shifts of the peaks and the CWL in the transmission spectrum of the SFS structure, this study has shown that this approach forms the basis of effective designs of high sensitivity sensors for multi-parameter detection and offering a large measurement range to satisfy the requirements needed for better industrial measurements