Propagation of light in a highly scattering medium is among the most fascinating optical effect that everyone experiences on an everyday basis and possesses a number of fundamental problems which have yet to be solved. Conventional wisdom suggests th
at non-linear effects do not play a significant role because the diffusive nature of scattering acts to spread the intensity, dramatically weakening these effects. We demonstrate the first experimental evidence of lasing on a Raman transition in a bulk three-dimensional random media. From a practical standpoint, Raman transitions allow for spectroscopic analysis of the chemical makeup of the sample. A random Raman laser could serve as a bright Raman source allowing for remote, chemically specific, identification of powders and aerosols. Fundamentally, the first demonstration of this new light source opens up an entire new field of study into non-linear light propagation in turbid media, with the most notable application related to non-invasive biomedical imaging.
In the minimal supersymmetric extension of the Standard Model (MSSM), if the two Higgs doublets are lighter than some subset of the superpartners of the Standard Model particles, then it is possible to integrate out the heavy states to obtain an effe
ctive broken-supersymmetric low-energy Lagrangian. This Lagrangian can contain dimension-four gauge invariant Higgs interactions that violate supersymmetry (SUSY). The wrong-Higgs Yukawa couplings generated by one-loop radiative corrections are a well known example of this phenomenon. In this paper, we examine gauge invariant gaugino--higgsino--Higgs boson interactions that violate supersymmetry. Such wrong-Higgs gaugino couplings can be generated in models of gauge-mediated SUSY-breaking in which some of the messenger fields couple to the MSSM Higgs bosons. In regions of parameter space where the messenger scale is low and tan(beta) is large, these hard SUSY-breaking operators yield tan(beta)-enhanced corrections to tree-level supersymmetric relations in the chargino and neutralino sectors that can be as large as 20%. We demonstrate how physical observables in the chargino sector can be used to isolate the tan(beta)-enhanced effects derived from the wrong-Higgs gaugino operators.
