The Phenomena Of Rabi Spectral Broadening Under The Impact Of Colored Noise

The study of Rabi spectrum in two-level systems has attracted extensive attention recently.The interaction between single atoms and electromagnetic fields generated by high-quality oscillators constitutes the cornerstone of quantum optics,and Rabi spectrum analysis has also become a basic tool in many fields,such as physics,chemistry,and astronomy.In the process of atomic clock timing,the accuracy of clock decreases due to the instability of frequency and uncertainty of system so that the measurement is significant of the Rabi spectrum of the two-level system to lock the oscillator.Noise affects the measurement of Rabi spectrum.In this paper,the Rabi spectrum of a two-level system with noise is numerically simulated to study the broadening of the system under the influence of colored noise.In this paper,the development process of Rabi model and the application of Rabi spectrum in various fields are introduced firstly.Especially in the frequency locking process of atomic clock,the Rabi spectrum plays an important role.The influence of noise on atomic clock system is also discussed.Then,several common noise classification standards are introduced.According to the different slopes of the noise power spectrum in the double logarithmic coordinate system,the noise can be divided into different colored noise with different time correlation characteristics.The calculation method of the noise power spectrum and the process of spectrum analysis by the fast Fourier transform method are introduced in detail.Then the noise term is introduced into the Hamiltonian of a two-level atomic system interacting with light,and the time-dependent Schrodinger equation with noise is obtained.The fourth order Runge-Kuta method is used to numerically solve the Schrodinger equation to simulate the evolution of the two-level system with time under the influence of noise.We select 1/f noise,white noise and brown noise with different time correlation characteristics,and change the noise amplitude,noise type and measurement time by using the control variable method.Under the above conditions,calculating the Rabi spectrum and its halfwidth of the atomic clock system with noise,so as to obtain the influence of different variables on the Rabi spectrum broadening.The results show that for the same kind of noise,the half-width of Rabi spectrum becomes wider when the noise amplitude is increased at the same measurement time.Under the condition of the same noise amplitude,colored noise with a greater degree of time correlation can make the Rabi spectrum broaden more obviously.When other conditions remain unchanged,the broadening of Rabi spectrum becomes more sensitive to noise amplitude by extending the measurement time.In conclusion,the noise can broaden the Rabi spectrum for the increasing of noise amplitude,and affect the measurement accuracy of the spectrum.When the measurement time does not exceed the value π/θ,the broadening of the Rabi spectrum becomes smaller,and is more sensitive to the noise amplitude.The brown noise containing more lowfrequency components can make the full width at half maximum of the Rabi spectrum wider.This work has some research value and serves as a standard for determining the Rabi spectrum under time-dependent noise in real-world applications.