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991.
992.
Stewart C Zieminski A Blessing S Crittenden R Draper P Dzierba A Heinz R Krider J Marshall T Martin J Sambamurti A Smith P Sulanke T Gomez R Dauwe L Haggerty H Malamud E Nikolic M Hagopian S Abrams R Ares J Goldberg H Halliwell C Margulies S McLeod D Salminen A Solomon J Wu G Ellsworth R Goodman J Gupta S Yodh G Watts T Abramov V Antipov Y Baldin B Denisov S Glebov V Gorin Y Kryshkin V Petrukhin A Polovnikov S Sulyaev R 《Physical review D: Particles and fields》1990,42(5):1385-1395
993.
Systems consisting of identical bosons with a large scattering length satisfy universal relations determined by 2-body physics that are similar to those for fermions with two spin states. They require the momentum distribution to have a large-momentum 1/k(4) tail and the radio-frequency transition rate to have a high-frequency 1/ω(3/2) tail, both of which are proportional to the 2-body contact. Identical bosons also satisfy additional universal relations that are determined by 3-body physics and involve the 3-body contact, which measures the probability of 3 particles being very close together. The coefficients of the 3-body contact in the 1/k(5) tail of the momentum distribution and in the 1/ω(2) tail of the radio-frequency transition rate are log-periodic functions of k and ω that depend on the Efimov parameter. 相似文献
994.
Mansuryan T Kalashyan M Lhermite J Suran E Kermene V Barthelemy A Louradour F 《Optics letters》2011,36(9):1635-1637
A very compact and innovative pulse shaper is proposed and demonstrated. The standard architecture for pulse shaping that is composed of diffraction gratings associated with an amplitude-phase spatial light modulator (SLM) is replaced by a single phase-only SLM. It acts as a pulse stretcher and as an amplitude and phase modulator at the same time. Preliminary experiments demonstrate the accurate control of amplitude and phase of shaped pulses. 相似文献
995.
We present a extended-cavity diode laser (ECDL) with kilohertz linewidth by optical feedback from a monolithic folded Fabry-Perot cavity (MFC). In our experiments, an MFC replaces the retroreflecting mirror in the traditional ECDL configuration. Beat-note measurements between this MFC-ECDL and a narrow-linewidth reference laser are performed and demonstrate that the linewidth of this MFC-ECDL is about 6.8 kHz. Phase locking of this MFC-ECDL to the reference laser is achieved with a unity gain as small as 10.2 kHz. 相似文献
996.
Khachatryan V Sirunyan AM Tumasyan A Adam W Bergauer T Dragicevic M Erö J Fabjan C Friedl M Frühwirth R Ghete VM Hammer J Hänsel S Hartl C Hoch M Hörmann N Hrubec J Jeitler M Kasieczka G Kiesenhofer W Krammer M Liko D Mikulec I Pernicka M Rohringer H Schöfbeck R Strauss J Taurok A Teischinger F Wagner P Waltenberger W Walzel G Widl E Wulz CE Mossolov V Shumeiko N Suarez Gonzalez J Benucci L Cerny K De Wolf EA Janssen X Maes T Mucibello L Ochesanu S Roland B Rougny R Selvaggi M Van Haevermaet H 《Physical review letters》2011,106(11):112001
Measurements of the total and differential cross sections dσ/dp(T)(B) and dσ/dy(B) for B(+) mesons produced in pp collisions at sqrt[s]=7 TeV are presented. The data correspond to an integrated luminosity of 5.8 pb(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B(+)→J/ψK(+), with J/ψ→μ(+)μ(-), is used to detect B(+) mesons and to measure the production cross section as a function of p(T)(B) and y(B). The total cross section for p(T)(B)>5 GeV and |y(B)|<2.4 is measured to be 28.1±2.4±2.0±3.1 μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement. 相似文献
997.
Pekker D Babadi M Sensarma R Zinner N Pollet L Zwierlein MW Demler E 《Physical review letters》2011,106(5):050402
We study the quench dynamics of a two-component ultracold Fermi gas from the weak into the strong interaction regime, where the short time dynamics are governed by the exponential growth rate of unstable collective modes. We obtain an effective interaction that takes into account both Pauli blocking and the energy dependence of the scattering amplitude near a Feshbach resonance. Using this interaction we analyze the competing instabilities towards Stoner ferromagnetism and pairing. 相似文献
998.
Shen NH Massaouti M Gokkavas M Manceau JM Ozbay E Kafesaki M Koschny T Tzortzakis S Soukoulis CM 《Physical review letters》2011,106(3):037403
We experimentally demonstrate, for the first time, an optically implemented blueshift tunable metamaterial in the terahertz (THz) regime. The design implies two potential resonance states, and the photoconductive semiconductor (silicon) settled in the critical region plays the role of intermediary for switching the resonator from mode 1 to mode 2. The observed tuning range of the fabricated device is as high as 26% (from 0.76 THz to 0.96 THz) through optical control to silicon. The realization of broadband blueshift tunable metamaterial offers opportunities for achieving switchable metamaterials with simultaneous redshift and blueshift tunability and cascade tunable devices. Our experimental approach is compatible with semiconductor technologies and can be used for other applications in the THz regime. 相似文献
999.
Andresen GB Ashkezari MD Baquero-Ruiz M Bertsche W Bowe PD Butler E Carpenter PT Cesar CL Chapman S Charlton M Fajans J Friesen T Fujiwara MC Gill DR Hangst JS Hardy WN Hayden ME Humphries AJ Hurt JL Hydomako R Jonsell S Madsen N Menary S Nolan P Olchanski K Olin A Povilus A Pusa P Robicheaux F Sarid E Silveira DM So C Storey JW Thompson RI van der Werf DP Wurtele JS Yamazaki Y;ALPHA Collaboration 《Physical review letters》2011,106(2):025002
We demonstrate controllable excitation of the center-of-mass longitudinal motion of a thermal antiproton plasma using a swept-frequency autoresonant drive. When the plasma is cold, dense, and highly collective in nature, we observe that the entire system behaves as a single-particle nonlinear oscillator, as predicted by a recent theory. In contrast, only a fraction of the antiprotons in a warm plasma can be similarly excited. Antihydrogen was produced and trapped by using this technique to drive antiprotons into a positron plasma, thereby initiating atomic recombination. 相似文献
1000.
Jewart CM Chen T Lindner E Fiebrandt J Rothhardt M Schuster K Kobelke J Bartelt H Chen KP 《Optics letters》2011,36(23):4491-4493
This Letter presents simulation and experimental results that explore bending insensitivity of fiber Bragg gratings in suspended-core optical fibers. The implementation of thin silica bridge in the fibers enhances index contrast of the fiber core and reduces bending-induced strain transfer to the fiber core. This fiber design lead to a reduction of over 7 times in strain-induced fiber Bragg grating resonant peak shifts in the suspended-core fiber compared with that in standard telecommunication fiber, and an 0.14 dB bending loss at a bending radius of 6.35 mm. 相似文献