电磁场的寖渐施加撤除与能量算符(英文)

Adiabatic Switching of Electromagnetic Fields and the Energy Operator

当电磁场(宀浸)渐施加并随后(宀浸)渐撤除之后,电磁场为零而矢势和标势仍可不为零。在这情形下必须用能量算符而不能用哈密顿量去计算系统处于一能量本征态的几率。在电磁场为零时势为零这种规范中,能量算符化为未扰动哈密顿量,这时能用通常的方法计算几率。

When the electromagnetic field is adiabatically switched on and subsequently switched off, the vector and scalar potentials can still be nonzero when the electromagnetic fiele is zero. In this case it is necessary to use the energy operator, not the Hamiltonian, to calculate the probability that the system is in an energy eigenstate. In the gauge in which the potentials are zero when the field is zero, the energy operator reduces to the unperturbed Hamiltonian and the usual procedure for calculating probabilities can be used.