We study the superfluid behavior of a population imbalanced ultracold atomic Fermi gases with a short range attractive interaction in a one-dimensional(1D)optical lattice,using a pairing fluctuation theory.We show tha...We study the superfluid behavior of a population imbalanced ultracold atomic Fermi gases with a short range attractive interaction in a one-dimensional(1D)optical lattice,using a pairing fluctuation theory.We show that,besides widespread pseudogap phenomena and intermediate temperature superfluidity,the superfluid phase is readily destroyed except in a limited region of the parameter space.We find a new mechanism for pair hopping,assisted by the excessive majority fermions,in the presence of continuum-lattice mixing,which leads to an unusual constant Bose-Einstein condensate(BEC)asymptote for Tc that is independent of pairing strength.In result,on the BEC side of unitarity,superfluidity,when it exists,may be strongly enhanced by population imbalance.展开更多
It has been an important goal to achieve higher or even room temperature superconductivity,since the discovery of high Tc superconductors in 1986,with a typical maximum transition temperature Tc of around 95 K at ambi...It has been an important goal to achieve higher or even room temperature superconductivity,since the discovery of high Tc superconductors in 1986,with a typical maximum transition temperature Tc of around 95 K at ambien pressure[1]or up to 164 K for the Hg-based cuprates under high pressure[2].The typical Tc/TF is only around 0.05 or less,where TF denotes the Fermi temperature.There have been a few other families of superconductors,including the iron-based[3],heavy fermion[4]and organic superconductors[5].Their maximum attainable Tc/TF has not been able to exceed that of the cuprates.Other notable superconductors include the recently discovered H2S with a record high Tc=203 K under an enormous high pressure of 90 GPa[6],and the monolayer FeSe/SrTiO3 superconductors with a gap opening temperature up to 100 K[7].展开更多
基金National Natural Science Foundation of China(Grant Nos.11774309 and 11674283)Natural Science Foundation of Zhejiang Province of China(Grant No.LZ13A040001)。
文摘We study the superfluid behavior of a population imbalanced ultracold atomic Fermi gases with a short range attractive interaction in a one-dimensional(1D)optical lattice,using a pairing fluctuation theory.We show that,besides widespread pseudogap phenomena and intermediate temperature superfluidity,the superfluid phase is readily destroyed except in a limited region of the parameter space.We find a new mechanism for pair hopping,assisted by the excessive majority fermions,in the presence of continuum-lattice mixing,which leads to an unusual constant Bose-Einstein condensate(BEC)asymptote for Tc that is independent of pairing strength.In result,on the BEC side of unitarity,superfluidity,when it exists,may be strongly enhanced by population imbalance.
基金supported by the National Natural Science Foundation of China(Grant Nos.11274267,and 11774309)the National Basic Research Program of China(Grant No.2012CB927404)Natural Science Foundation of Zhejiang Province of China(Grant No.LZ13A040001)
文摘It has been an important goal to achieve higher or even room temperature superconductivity,since the discovery of high Tc superconductors in 1986,with a typical maximum transition temperature Tc of around 95 K at ambien pressure[1]or up to 164 K for the Hg-based cuprates under high pressure[2].The typical Tc/TF is only around 0.05 or less,where TF denotes the Fermi temperature.There have been a few other families of superconductors,including the iron-based[3],heavy fermion[4]and organic superconductors[5].Their maximum attainable Tc/TF has not been able to exceed that of the cuprates.Other notable superconductors include the recently discovered H2S with a record high Tc=203 K under an enormous high pressure of 90 GPa[6],and the monolayer FeSe/SrTiO3 superconductors with a gap opening temperature up to 100 K[7].
