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91.
A spinor () Bose gas is studied in presence of a density‐density interaction through a mean field approach and a perturbation theory for either sign of the spin dependent interaction, namely the antiferromagnetic (AF) and the ferromagnetic cases. In the AF case, the charge density wave (CDW) phase appears to be sandwiched between the Mott insulating (MI) and the supersolid phases for small values of the extended interaction strength. But the CDW phase completely occupies the MI lobe when the extended interaction strength is larger than a certain critical value related to the width of the MI lobes and hence opens up the possibilities of spin singlet and nematic CDW insulating phases. In the ferromagnetic case, the phase diagram shows similar features as that of the AF case and are in complete agreement with a spin‐0 Bose gas. The perturbation expansion calculations nicely corroborate the mean field phase results in both these cases. Further, we extend our calculations in presence of a harmonic confinement and obtained the momentum distribution profile that is related to the absorption spectra in order to distinguish between different phases. 相似文献
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Priyadarshini Kapri Saurabh Basu 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(2):33
The tunneling conductance for a junction device consisting of a normal metal and a singlet superconductor is studied with Rashba spin orbit coupling (RSOC) being present in the metallic lead and the interface separating the two regions via an extended Blonder-Tinkham-Klapwijk (BTK) formalism. Interesting interplay between the RSOC and a number of parameters that have experimental significance, and characterize either the junction or the superconducting leads, such as the barrier transparency, quasiparticle lifetime, Fermi wavevector mismatch, an in-plane magnetic field and their effects on the tunneling conductance are investigated in details for both a s-wave and a d-wave superconductor. In an opaque barrier, in presence of a quasiparticle lifetime, a Fermi wavevector mismatch or an external in-plane magnetic field, RSOC enhances the conductance corresponding to low biasing energies, that is, at energies lesser than the superconducting gap, while the reverse is noted for energies exceeding the magnitude of the gap. Further, there are exciting anomalies noted in the conductance spectrum for the d-wave gap which can be understood by incorporating the interplay between the superconducting gap and the angle of incident of the charge carriers. 相似文献
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Establishing the Coordination Chemistry of Antimony(V) Cations: Systematic Assessment of Ph4Sb(OTf) and Ph3Sb(OTf)2 as Lewis Acceptors 下载免费PDF全文
Dr. Alasdair P. M. Robertson Saurabh S. Chitnis Dr. Hilary A. Jenkins Dr. Robert McDonald Dr. Michael J. Ferguson Prof. Neil Burford 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7902-7913
The coordination chemistry of the stiboranes Ph4Sb(OTf) ( 1 a , OTf = OSO2CF3) and Ph3Sb(OTf)2 ( 3 ) with Lewis bases has been investigated. The significant steric encumbrance of the Sb center in 1 a precludes interaction with most ligands, but the relatively low steric demands of 4‐methylpyridine‐N‐oxide (OPyrMe) and OPMe3 enabled the characterization of [Ph4Sb(OPyrMe)][OTf] ( 2 a ) and [Ph4Sb(OPMe3)][OTf] ( 2 b ), rare examples of structurally characterized complexes of stibonium acceptors. In contrast, 3 was found to engage a variety of Lewis bases, forming stable isolable complexes of the form [Ph3Sb(donor)2][OTf]2 [donor=OPMe3 ( 6 a ), OPCy3 ( 6 b , Cy=cyclohexyl), OPPh3 ( 6 c ), OPyrMe ( 6 d )], [Ph3Sb(dmap)2(OTf)][OTf] ( 6 e , dmap=4‐(dimethylamino)pyridine) and [Ph3Sb(donor)(OTf)][OTf] [donor=1,10‐phenanthroline ( 7 a ) or 2,2′‐bipy ( 7 b , bipy=bipyridine)]. These compounds exhibit significant structural diversity in the solid‐state, and undergo ligand exchange reactions in line with their assignment as coordination complexes. Compound 3 did not form stable complexes with phosphine donors, with reactions instead leading to redox processes yielding SbPh3 and products of phosphine oxidation. 相似文献
96.
Srubabati Goswami Raghavan Rangarajan K. Agashe A. Bandyopadhyay K. Bhattacharya B. Brahmachari C. Burgess E. J. Chun D. Choudhury P. K. Das A. Dighe R. Godbole S. Goswami N. Gupta M. Kaplinghat D. Indumathi J. Forshaw Y. Y. Keum B. Layek D. Majumdar N. Mahajan P. Mehta R. N. Mohapatra N. Mondai S. More Y. Nir S. Pakvasa M. K. Parida M. Ravikumar G. Rajasekaran P. Ramadevi R. Rangarajan S. D. Rindani D. P. Roy P. Roy N. Sahu A. Samanta Y. Shadmi A. M. Srivastava S. Uma Sankar R. Vaidya U. Yajnik 《Pramana》2004,63(6):1391-1405
This is the report of neutrino and astroparticle physics working group at WHEPP-8. We present the discussions carried out
during the workshop on selected topics in the above fields and also indicate progress made subsequently. The neutrino physics
subgroup studied the possibilities of constraining neutrino masses, mixing and CPT violation in lepton sector from future
experiments. Neutrino mass models in the context of Abelian horizontal symmetries, warped extra dimensions and in the presence
of triplet Higgs were studied. Effect of threshold corrections on radiative magnification of mixing angles was investigated.
The astroparticle physics subgroup focused on how various particle physics inputs affect the CMBR fluctuation spectrum, and
on brane cosmology. This report also contains an introduction on how to use the publicly available code CMBFAST to calculate
the CMBR fluctuations. 相似文献
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Podophyllotoxin was produced by cell culture of Podophyllum hexandrum under in vitro culture conditions. A maximum of 4.26 mg/L of podophyllotoxin was produced when P. hexandrum was cultivated in 3 L stirred tank bioreactor. The compound extracted from the cell culture was applied to the human breast cancer cell line (MCF-7) and 1 nM podophyllotoxin was able to inhibit the growth of the cancer cells by 50%. The most profound inhibitory effect of podophyllotoxin was observed when it was applied in the beginning of cell growth. 相似文献
100.