19,111 research outputs found
Condensates induced by interband coupling in a double-well lattice
We predict novel inter-band physics for bosons in a double-well lattice. An
intrinsic coupling between the s and px band due to interaction gives rise to
larger Mott regions on the phase diagram at even fillings than the ones at odd
fillings. On the other hand, the ground state can form various types of
condensates, including a mixture of single-particle condensates of both bands,
a mixture of a single-particle condensate of one band and a pair-condensate of
the other band, and a pair-condensate composed of one particle from one band
and one hole from the other band. The predicted phenomena should be observable
in current experiments on double-well optical lattices.Comment: Published versio
Autonomous absolute calibration of an ICCD camera in single-photon detection regime
Intensified charge coupled device (ICCD) cameras are widely used in various
applications such as microscopy, astronomy, spectroscopy. Often they are used
as single-photon detectors, with thresholding being an essential part of the
readout. In this paper, we measure the quantum efficiency of an ICCD camera in
the single-photon detection mode using the Klyshko absolute calibration
technique. The quantum efficiency is obtained as a function of the threshold
value and of the wavelength of the detected light. In addition, we study the
homogeneity of the photon sensitivity over the camera chip area. The experiment
is performed in the autonomous regime, without using any additional detectors.
We therefore demonstrate the self-calibration of an ICCD camera.Comment: 8 pages, 3 figure
A New Solution of the Yang-Baxter Equation Related to the Adjoint Representation of
A new solution of the Yang-Baxter equation, that is related to the adjoint
representation of the quantum enveloping algebra , is obtained by
fusion formulas from a non-standard solution.Comment: 16 pages (Latex), Preprint BIHEP-TH-93-3
Large deviations for local times and intersection local times of fractional Brownian motions and Riemann-Liouville processes
In this paper we prove exact forms of large deviations for local times and
intersection local times of fractional Brownian motions and Riemann-Liouville
processes. We also show that a fractional Brownian motion and the related
Riemann-Liouville process behave like constant multiples of each other with
regard to large deviations for their local and intersection local times. As a
consequence of our large deviation estimates, we derive laws of iterated
logarithm for the corresponding local times. The key points of our methods: (1)
logarithmic superadditivity of a normalized sequence of moments of
exponentially randomized local time of a fractional Brownian motion; (2)
logarithmic subadditivity of a normalized sequence of moments of exponentially
randomized intersection local time of Riemann-Liouville processes; (3)
comparison of local and intersection local times based on embedding of a part
of a fractional Brownian motion into the reproducing kernel Hilbert space of
the Riemann-Liouville process.Comment: To appear in the Annals of Probabilit
Interaction-induced excited-band condensate in a double-well optical lattice
We show theoretically that interaction effects in a double-well optical
lattice can induce condensates in an excited band. For a symmetric double-well
lattice, bosons condense into the bottom of the excited band at the edge of the
Brillouin Zone if the chemical potential is above a critical value. For an
asymmetric lattice, a condensate with zero momentum is automatically induced in
the excited band by the condensate in the lowest band. This is due to a
combined effect of interaction and lattice potential, which reduces the band
gap and breaks the inversion symmetry. Our work can be generalized to a
superlattice composed of multiple-well potentials at each lattice site, where
condensates can be induced in even higher bands.Comment: 4pages, 3 figure
Evaluating Responses of Sugar Beet Cultivars to Fusarium Species in Greenhouse and Field Conditions
Fusarium yellows of sugar beet (Beta vulgaris L.) is becoming an important disease in Minnesota and North Dakota in the United States. One of the best ways to manage Fusarium yellows is to develop and use resistant cultivars. Responses of eight sugar beet cultivars to three Fusarium species were determined in the greenhouse and compared to the responses of the same eight cultivars grown in a field already infected by Fusarium yellows. There were significant and appreciable relationships between greenhouse and field studies for responses of eight sugar beet cultivars on Fusarium yellows. The estimated correlation coefficient for area under disease progress curve (AUDPC) between observations in fields and those in greenhouses was 0.987 (p<0.01). The mean AUDPC were significantly different among cultivars (p<0.01) in the greenhouse and in the field studies. Of the cultivars, Van der Have 46177 was the most susceptible, but Crystal R434 the most resistant. Crystal 820, Van der Have 66561, and Beta 4797R were resistant, and Beta 4818R, Seedex Magnum, and Hilleshog 2463Rz were moderately resistant. There was a strong negative relationship between the AUDPC and recoverable sucrose yield in the field experiments and the estimated coefficient of determination was 0.939 (p<0.01). It was concluded that greenhouse screening can act as a useful and reliable means to evaluate and select beet germplasms and/or accessions for resistance to Fusarium yellows.Peer reviewe
- …