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41.
We present theoretical results that demonstrate a new technique that can be used to improve the sensitivity of thermal noise measurements: intracavity intensity stabilization. It is demonstrated that electro-optic feedback can be used to reduce intracavity intensity fluctuations, and the consequent radiation pressure fluctuations, by a factor of 2 below the quantum-noise limit. We show that this reduction is achievable in the presence of large classic intensity fluctuations in the incident laser beam. The benefits of this scheme are a consequence of the sub-Poissonian intensity statistics of the field inside a feedback loop and the quantum nondemolition nature of radiation pressure noise as a readout system for the intracavity intensity fluctuations. 相似文献
42.
Chakhalian J Rondinelli JM Liu J Gray BA Kareev M Moon EJ Prasai N Cohn JL Varela M Tung IC Bedzyk MJ Altendorf SG Strigari F Dabrowski B Tjeng LH Ryan PJ Freeland JW 《Physical review letters》2011,107(11):116805
Using resonant x-ray spectroscopies combined with density functional calculations, we find an asymmetric biaxial strain-induced d-orbital response in ultrathin films of the correlated metal LaNiO3 which are not accessible in the bulk. The sign of the misfit strain governs the stability of an octahedral "breathing" distortion, which, in turn, produces an emergent charge-ordered ground state with an altered ligand-hole density and bond covalency. Control of this new mechanism opens a pathway to rational orbital engineering, providing a platform for artificially designed Mott materials. 相似文献
43.
Jaffe DE Straub PB Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Glass HD Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review D: Particles and fields》1989,40(9):2777-2795
44.
Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Brock IC Ferguson T Artuso M Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Crawford G DeSalvo R DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Silverman A Stone S Worden H 《Physical review letters》1989,62(21):2436-2439
45.
46.
Alam MS Katayama N Kim IJ Li WC Lou XC Sun CR Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Brock IC Ferguson T Artuso M Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Crawford G DeSalvo R DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M 《Physical review D: Particles and fields》1989,40(11):3790
47.
It is suggested that the question of existence of a jamming phase transition in a broad class of single-lane cellular-automaton traffic models may be studied using a correspondence to the asymmetric chipping model. In models where such correspondence is applicable, jamming phase transition does not take place. Rather, the system exhibits a smooth crossover between free-flow and jammed states, as the car density is increased. 相似文献
48.
Recently, unusual giant magnetic properties were found experimentally in some organized organic monolayers adsorbed on solid substrates. A model is presented which explains the observed phenomenon. The model is based on the special properties of electrons transferred from the substrate to the layer as a result of the adsorption process. Triplet pairing of those electrons is forced by the special 2D properties of the organic layer. Such pairs are confined within domains in the organic layer and their quantum statistics provide a model that explains the unique magnetization as well as all other features of the experimental observations. The model suggests the possible existence of Bose-Einstein condensation at room temperature on the scale of the domains. 相似文献
49.
Pump-probe differencing technique for cavity-enhanced, noise-canceling saturation laser spectroscopy
We present an experimental technique that permits mechanical-noise-free, cavity-enhanced frequency measurements of an atomic transition and its hyperfine structure. We employ the 532-nm frequency-doubled output from a Nd:YAG laser and an iodine vapor cell. The cell is placed in a folded ring cavity (FRC) with counterpropagating pump and probe beams. The FRC is locked with the Pound-Drever-Hall technique. Mechanical noise is rejected by differencing the pump and probe signals. In addition, this differenced error signal provides a sensitive measure of differential nonlinearity within the FRC. 相似文献
50.
Coan TE Gao YS Liu F Maravin Y Stroynowski R Artuso M Boulahouache C Blusk S Bukin K Dambasuren E Moneti GC Mountain R Muramatsu H Nandakumar R Skwarnicki T Stone S Wang JC Mahmood AH Csorna SE Danko I Bonvicini G Cinabro D Dubrovin M McGee S Bornheim A Lipeles E Pappas SP Shapiro A Sun WM Weinstein AJ Briere RA Chen GP Ferguson T Tatishvili G Vogel H Adam NE Alexander JP Berkelman K Boisvert V Cassel DG Drell PS Duboscq JE Ecklund KM Ehrlich R Galik RS Gibbons L Gittelman B Gray SW Hartill DL 《Physical review letters》2003,90(10):101801
Using 13.8 fb(-1) of data collected at or just below the Upsilon(4S) with the CLEO detector, we report the result of a search for the flavor changing neutral current process D0-->gammagamma. We observe no significant signal for this decay mode and determine 90% confidence level upper limits on the branching fractions B(D0-->gammagamma)/B(D0-->pi(0)pi(0))<0.033 and B(D0-->gammagamma)<2.9 x 10(-5). 相似文献