4,794 research outputs found
125 GeV Higgs as a pseudo-Goldstone boson in supersymmetry with vector-like matters
We propose a possibility of the 125 GeV Higgs being a pseudo-Goldstone boson
in supersymmetry with extra vector-like fermions. Higgs mass is obtained from
loops of top quark and vector-like fermions from the global symmetry breaking
scale f at around TeV. The mu, Bmu/mu \sim f are generated from the dynamics of
global symmetry breaking and the Higgs quartic coupling vanishes at f as tan
beta \simeq 1. The relation of msoft \sim with f \sim mu \sim m_soft
\sim TeV is obtained and large mu does not cause a fine tuning for the
electroweak symmetry breaking. The Higgs to di-photon rate can be enhanced from
the loop of uncolored vector-like matters. The stability problem of Higgs
potential with vector-like fermions can be nicely cured by the UV completion
with the Goldstone picture.Comment: 28 pages, 8 figure
Competing Magnetic Orderings and Tunable Topological States in Two-Dimensional Hexagonal Organometallic Lattices
The exploration of topological states is of significant fundamental and
practical importance in contemporary condensed matter physics, for which the
extension to two-dimensional (2D) organometallic systems is particularly
attractive. Using first-principles calculations, we show that a 2D hexagonal
triphenyl-lead lattice composed of only main group elements is susceptible to a
magnetic instability, characterized by a considerably more stable
antiferromagnetic (AFM) insulating state rather than the topologically
nontrivial quantum spin Hall state proposed recently. Even though this AFM
phase is topologically trivial, it possesses an intricate emergent degree of
freedom, defined by the product of spin and valley indices, leading to Berry
curvature-induced spin and valley currents under electron or hole doping.
Furthermore, such a trivial band insulator can be tuned into a topologically
nontrivial matter by the application of an out-of-plane electric field, which
destroys the AFM order, favoring instead ferrimagnetic spin ordering and a
quantum anomalous Hall state with a non-zero topological invariant. These
findings further enrich our understanding of 2D hexagonal organometallic
lattices for potential applications in spintronics and valleytronics.Comment: 9 pages, 8 figure
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