Nuclear masses ranging from O to Ti isotopes are systematically investigated with relativistic continuum Hartree-Bogoliubov(RCHB)theory,which can provide a proper treatment of pairing correlations in the presence of t...Nuclear masses ranging from O to Ti isotopes are systematically investigated with relativistic continuum Hartree-Bogoliubov(RCHB)theory,which can provide a proper treatment of pairing correlations in the presence of the continuum.From O to Ti isotopes,there are 402 nuclei predicted to be bound by the density functional PC-PK1.For the 234 nuclei with mass measured,the root mean square(rms)deviation is 2.23 MeV.It is found that the proton drip-lines predicted with various mass models are roughly the same and basically agree with the observation.The neutron drip-lines predicted,however,are quite diferent.Due to the continuum couplings,the neutron drip-line nuclei predicted are extended further neutron-rich than other mass models.By comparison with finite-range droplet model(FRDM),the neutron drip-line nucleus predicted by RCHB theory has respectively2(O),10(Ne),10(Na),6(Mg),8(Al),6(Si),8(P),6(S),14(K),10(Ca),10(Sc),and 12(Ti)more neutrons.展开更多
In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is investigated.For this purpose,we first have used the density functional theory(DFT) to calculate the electron and...In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is investigated.For this purpose,we first have used the density functional theory(DFT) to calculate the electron and hole effective masses.Then,we have obtained absorption threshold energy with two different procedures,DFT and effective mass approximation(EMA).We have also obtained the band structures of Si nanowires both DFT and EMA.The results show that:i) the expansive strain increases the hole effective mass while compressive strain increases the electron effective mass,ii) the electron and hole effective masses reduce with decreasing the wire size,iii) the absorption threshold energy decreases by increasing strain for compressive and tensile strain and its behavior as a function of strain is approximately parabolic,iv) the absorption threshold energy(for all sizes) obtained using EMA is greater than the DFT results.展开更多
基金partially supported by the Major State Basic Research Development Program of China (Grant No. 2013CB834400)National Natural Science Foundation of China (Grant Nos. 11335002, 11345004, 11375015, 11105005, 11105006 and 11175002)+4 种基金China Postdoctoral Science Foundation (Grant Nos. 2012M520101 and 2013T60022)the Research Fund for the Doctoral Program of Higher Education (Grant No. 20110001110087)the support of the Young Core Instructor and Domestic Visitor Foundation from the Wuhan Center of Teacher Education Exchangesupported by the Rare Isotope Science Project funded by the Ministry of Science, ICT and Future Planning (MSIP) and National Research Foundation of Koreasupported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (Grant No. 2010-0023661)
文摘Nuclear masses ranging from O to Ti isotopes are systematically investigated with relativistic continuum Hartree-Bogoliubov(RCHB)theory,which can provide a proper treatment of pairing correlations in the presence of the continuum.From O to Ti isotopes,there are 402 nuclei predicted to be bound by the density functional PC-PK1.For the 234 nuclei with mass measured,the root mean square(rms)deviation is 2.23 MeV.It is found that the proton drip-lines predicted with various mass models are roughly the same and basically agree with the observation.The neutron drip-lines predicted,however,are quite diferent.Due to the continuum couplings,the neutron drip-line nuclei predicted are extended further neutron-rich than other mass models.By comparison with finite-range droplet model(FRDM),the neutron drip-line nucleus predicted by RCHB theory has respectively2(O),10(Ne),10(Na),6(Mg),8(Al),6(Si),8(P),6(S),14(K),10(Ca),10(Sc),and 12(Ti)more neutrons.
文摘In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is investigated.For this purpose,we first have used the density functional theory(DFT) to calculate the electron and hole effective masses.Then,we have obtained absorption threshold energy with two different procedures,DFT and effective mass approximation(EMA).We have also obtained the band structures of Si nanowires both DFT and EMA.The results show that:i) the expansive strain increases the hole effective mass while compressive strain increases the electron effective mass,ii) the electron and hole effective masses reduce with decreasing the wire size,iii) the absorption threshold energy decreases by increasing strain for compressive and tensile strain and its behavior as a function of strain is approximately parabolic,iv) the absorption threshold energy(for all sizes) obtained using EMA is greater than the DFT results.
