The low-lying spectra of parabolic quantum dots with or without an impurity at the center are investigated.
While it has been known that the electron-electron interaction leads to ground-state transitions on magic val...The low-lying spectra of parabolic quantum dots with or without an impurity at the center are investigated.
While it has been known that the electron-electron interaction leads to ground-state transitions on magic values of angular
momentum in a magnetic field. We show, in this paper, that the implantation of an impurity ion at the center can either
enhance or suppress such transitions, depending on whether it is an acceptor or a donor ion.展开更多
Impurity scattering in a superconductor may serve as an important probe for the nature of superconducting pairing state. Here we report the impurity effect on superconducting transition temperature T c in the newly di...Impurity scattering in a superconductor may serve as an important probe for the nature of superconducting pairing state. Here we report the impurity effect on superconducting transition temperature T c in the newly discovered Cr-based superconductor K_2Cr_3As_3.The resistivity measurements show that the crystals prepared using high-purity Cr metal(99.99%) have an electron mean free path much larger than the superconducting coherence length. For the crystals prepared using impure Cr that contains various nonmagnetic impurities, however, the T c decreases significantly, in accordance with the generalized Abrikosov-Gor'kov pair-breaking theory. This finding supports a non-s-wave superconductivity in K_2Cr_3As_3.展开更多
基金supported by National Key R&D Program of China(Grant No.2022YFA1403201)National Natural Science Foundation of China(Grant No.12274205 and No.11874205).
文摘The low-lying spectra of parabolic quantum dots with or without an impurity at the center are investigated.
While it has been known that the electron-electron interaction leads to ground-state transitions on magic values of angular
momentum in a magnetic field. We show, in this paper, that the implantation of an impurity ion at the center can either
enhance or suppress such transitions, depending on whether it is an acceptor or a donor ion.
基金supported by the National Natural Science Foundation of China (Grant No. 11190023)the National Basic Research Program (Grant Nos. 2011CBA00103 and 2012CB927404)the Fundamental Research Funds for the Central Universities of China
文摘Impurity scattering in a superconductor may serve as an important probe for the nature of superconducting pairing state. Here we report the impurity effect on superconducting transition temperature T c in the newly discovered Cr-based superconductor K_2Cr_3As_3.The resistivity measurements show that the crystals prepared using high-purity Cr metal(99.99%) have an electron mean free path much larger than the superconducting coherence length. For the crystals prepared using impure Cr that contains various nonmagnetic impurities, however, the T c decreases significantly, in accordance with the generalized Abrikosov-Gor'kov pair-breaking theory. This finding supports a non-s-wave superconductivity in K_2Cr_3As_3.
