A ug 1 99 8 An Adiabatic Theorem without a Gap Condition : Two level system coupled to quantized radiation field
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چکیده
We prove an adiabatic theorem for the ground state of the Dicke model in a slowly rotating magnetic field and show that for weak electron-photon coupling , the adiabatic time scale is close to the time scale of the corresponding two level system–without the quantized radiation field. There is a correction to this time scale which is the Lamb shift of the model. The photon field affects the rate of approach to the adiabatic limit through a logarithmic correction originating from an infrared singularity characteristic of QED.
منابع مشابه
m at h . FA ] 1 9 A ug 1 99 8 An Adiabatic Theorem without a Gap Condition : Two level system coupled to quantized radiation field
We prove an adiabatic theorem for the ground state of the Dicke model in a slowly rotating magnetic field and show that for weak electron-photon coupling , the adiabatic time scale is close to the time scale of the corresponding two level system–without the quantized radiation field. There is a correction to this time scale which is the Lamb shift of the model. The photon field affect the rate ...
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