Degenerate Gases of Strontium for Studies of Quantum Magnetism

We describe the construction and characterization of a new apparatus that can produce degenerate quantum gases of strontium. The realization of degenerate gases is an important first step toward future studies of quantum magnetism. Three of the four stable isotopes of strontium have been cooled into the degenerate regime. The experiment can make nearly pure Bose-Einstein condensates containing approximately 1x10^4 atoms, for strontium-86, and approximately 4x10^5 atoms, for strontium-84. We have also created degenerate Fermi gases of strontium-87 with a reduced temperature, T/T_F of approximately 0.2. The apparatus will be able to produce Bose-Einstein condensates of strontium-88 with straightforward modifications. We also report the first experimental and theoretical results from the strontium project. We have developed a technique to accelerate the continuous loading of strontium atoms into a magnetic trap. By applying a laser addressing the 3P1 to 3S1 transition in our magneto-optical trap, the rate at which atoms populate the magnetically-trapped 3P2 state can be increased by up to 65%. Quantum degenerate gases of atoms in the metastable 3P0 and 3P2 states are a promising platform for quantum simulation of systems with long-range interactions. We have performed an initial numerical study of a method to transfer the ground state degenerate gases that we can currently produce into one of the metastable states via a three-photon transition. Numerical simulations of the Optical Bloch equations governing the three-photon transition indicate that >90% of a ground state degenerate gas can be transferred into a metastable state.

DEGENERATE MUSIC?! MUSICAL CENSORSHIP IN THE THIRD REICH

In 1938, in Düsseldorf, the Nazis put on an exhibit entitled "Entartete Musik” (degenerate music), which included composers on the basis of their “racial origins” (i.e. Jews), or because of the “modernist style” of their music. Performance, publication, broadcast, or sale of music by composers deemed “degenerate” was forbidden by law throughout the Third Reich. Among these composers were some of the most prominent composers of the first half of the twentieth-century. They included Stravinsky, Schoenberg, Webern, Berg, Mahler, Ernst Krenek, George Gershwin, Kurt Weill, Erwin Schulhoff, and others. The music of nineteenth-century composers of Jewish origin, such as Mendelssohn and Meyerbeer, was also officially proscribed. In each of the three recitals for this project, significant works were performed by composers who were included in this exhibition, namely, Mendelssohn, Webern, Berg, Weill, and Hans Gal. In addition, as an example of self-censorship, a work of Karl Amadeus Hartmann was included. Hartmann chose “internal exile” by refusing to allow performance of his works in Germany during the Nazi regime. One notable exception to the above categories was a work by Beethoven that was presented as a bellwether of the relationship between music and politics. The range of styles and genres in these three recitals indicates the degree to which Nazi musical censorship cut a wide swath across Europe’s musical life with devastating consequences for its music and culture.