The U-matrlx theory in quantum mechanics recently developed has been appliedto study a superconductor system described by the BCS pairing Hamiltonian . It is shown that in general the -operator in our theory specifies...The U-matrlx theory in quantum mechanics recently developed has been appliedto study a superconductor system described by the BCS pairing Hamiltonian . It is shown that in general the -operator in our theory specifies a canonical transformation. Using the to describe the system, it is proved that if the Hartrec type approximation is adopted, or the c-number approach is used, the Bogoliubov transformation can be derived via the U-matrix theory if the perturbing Hamiltonian is turned on ’suddenly’. It is also shown that based on the U-matrix, the BCS ground state wave function of a superconducting system can be deduced under the sudden switching condition.展开更多
文摘The U-matrlx theory in quantum mechanics recently developed has been appliedto study a superconductor system described by the BCS pairing Hamiltonian . It is shown that in general the -operator in our theory specifies a canonical transformation. Using the to describe the system, it is proved that if the Hartrec type approximation is adopted, or the c-number approach is used, the Bogoliubov transformation can be derived via the U-matrix theory if the perturbing Hamiltonian is turned on ’suddenly’. It is also shown that based on the U-matrix, the BCS ground state wave function of a superconducting system can be deduced under the sudden switching condition.