A new empirical model to estimate the content of sp^3 in diamond-like carbon （DLC） films is presented, based on the conventional Raman spectra excited by 488nm or 514nm visible light for different carbons. It is fou...A new empirical model to estimate the content of sp^3 in diamond-like carbon （DLC） films is presented, based on the conventional Raman spectra excited by 488nm or 514nm visible light for different carbons. It is found that bandwidth of the G peak is related to the sp^3 fraction. A wider bandwidth of the G peak shows a higher sp^3 fraction in DLC films.展开更多
We study theσmeson in 2+1 flavor full quantum chromodynamics(QCD)with sufficiently light u and d quarks.The point−to-point correlator is measured for theσchannel in the“Asqtad”improved staggered fermion formulatio...We study theσmeson in 2+1 flavor full quantum chromodynamics(QCD)with sufficiently light u and d quarks.The point−to-point correlator is measured for theσchannel in the“Asqtad”improved staggered fermion formulation.Particular attention is paid to its disconnected diagram and bubble contribution.After chiral extrapolation,we obtain theσmass with 706±53 MeV,which is close to the observedσmeson within error,and is heavier than theππthreshold.The simulations are carried out with MILC 2+1 flavor gauge configurations at lattice spacing of a≈0.15 fm.展开更多
文摘A new empirical model to estimate the content of sp^3 in diamond-like carbon （DLC） films is presented, based on the conventional Raman spectra excited by 488nm or 514nm visible light for different carbons. It is found that bandwidth of the G peak is related to the sp^3 fraction. A wider bandwidth of the G peak shows a higher sp^3 fraction in DLC films.
基金in part by the Fundamental Research Funds for the Central Universities under Grant No 2010SCU23002.
文摘We study theσmeson in 2+1 flavor full quantum chromodynamics(QCD)with sufficiently light u and d quarks.The point−to-point correlator is measured for theσchannel in the“Asqtad”improved staggered fermion formulation.Particular attention is paid to its disconnected diagram and bubble contribution.After chiral extrapolation,we obtain theσmass with 706±53 MeV,which is close to the observedσmeson within error,and is heavier than theππthreshold.The simulations are carried out with MILC 2+1 flavor gauge configurations at lattice spacing of a≈0.15 fm.
基金This work was financially sponsored by the National Natural Science Foundation of China （Grant No. 11205107） and the Ph.D. Program Foundation of Ministry of Education （Grant No. 20120181120063）.
