Detail Time-Resolved Observation and Control of Superexchange Interactions with Ultracold Atoms in Optical Lattices   Oleh:  Trotzky, S. ; Cheinet, P. ; Fölling, S. ; Feld, M. ; Schnorrberger, U. ; Rey, A.M. ; Polkovnikov, A. ; Demler, E.A. ; Lukin, M.D. ; Bloch, I. Jenis: Article from Bulletin/Magazine Dalam koleksi: SCIENCE (keterangan: ada di Proquest) vol. 319 no. 5861 (Jan. 2008), page 295. Ketersediaan Perpustakaan FK Nomor Panggil: S01.K.2008.01 Non-tandon: 1 (dapat dipinjam: 0) Tandon: tidak ada     Lihat Detail Induk Isi artikel Quantum mechanical superexchange interactions form the basis of quantum magnetism in strongly correlated electronic media. We report on the direct measurement of superexchange interactions with ultracold atoms in optical lattices. After preparing a spin-mixture of ultracold atoms in an antiferromagnetically ordered state, we measured coherent superexchange-mediated spin dynamics with coupling energies from 5 hertz up to 1 kilohertz. By dynamically modifying the potential bias between neighboring lattice sites, the magnitude and sign of the superexchange interaction can be controlled, thus allowing the system to be switched between antiferromagnetic and ferromagnetic spin interactions. We compare our findings to predictions of a two-site Bose-Hubbard model and find very good agreement, but are also able to identify corrections that can be explained by the inclusion of direct nearest-neighbor interactions. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Kembali

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