Study On The Motion Characteristics Of The Two-dimensional Electronic Gas Under Strong Electromagnetic Field With High Frequency

Many new phenomena are springing up in studying the interaction between light and matter,such as resistance oscillation and the zero resistance state of two-dimensional electron gas when radiated by microwave;The electroconductivity of two-dimensional electron gas radiated by strong light increased substantially,which can be up to many times of that without radiation;Higher order harmonic of microwave appears when the electron gas radiated by magnetic field and microwave.These phenomena and research results are all related to the interaction between the electromagnetic field and the electron.In view of the technical difficulty and limitation for achieving single high intensity magnetic field,we established the corresponding classical dynamic equations,according to the fact that strong magnetic field can be realized by ultra short ultra intense laser pulse and also considering right-hand helicity and orthogonality of laser.Based on these,we focused on the analytical solution of the corresponding dynamic equations of electron under three kinds of action,constant electric field,constant magnetic field and continuous laser and pulse laser.We also analyzed the motion characteristics of the related electron.Typical main results we have are as following:1.Considering the action of a constant and orthogonal electric and magnetic field,we find that the motion of the electron is two dimensional,and gave the curves of two dimensional motion by numerical simulations.And numerically analyzed the relationship between gyromagnetic frequency and light intensity.According to the calculating results,the cyclotron frequency is located in the range of terahertz frequency when light intensity reaches 9×10¹⁶-9×10²⁰W/m².When femtosecond laser intensity reaches the above range,the air can be ionized,and consequently femtosecond filament formed.This numerical result may be a kind of way in explaining the phenomenon of terahertz radiation in femtosecond filament;When light intensity reaches 1.74×10²⁵-6.32×10²⁵W/m²,the peak of the gyromagnetic frequency become to the visible range,that is to say,the free electrons radiate visible light wave under strong light.2.The corresponding dynamic equations of electron under continuous laser are studied by means of analytical solution,and a strict analytical solution of this equation is obtained.The analytic solution shows that the cyclotron frequency of the electron harmonically changed with the cycle electric field of light,and the peak amplitude of cyclotron frequency is proportional to the peak amplitude of the electric field.In addition,the numerical results show that higher order harmonic of the oscillation frequency of electron in the direction of electric field appeared with the increasing of laser intensity of continuous laser.This result may be used to study the micro mechanism of high order harmonic generation.Further numerical study show that resistivity of the two dimensional electron gas can be zero periodically.3.Take Gauss pulse laser as an example,we further studied the motion characteristics of two dimensional electron gas under the action of pulse laser.And obtained a rigorous analytical solution for the vibration velocity of electrons in the direction of the electric field under the action of Gauss pulse laser.According to the numerical results,with the change of the ratio of peak of electron cyclotron frequency to laser frequency,that is,for a fixed frequency pulse laser,the resistivity of the corresponding two dimensional electron gas showed great difference in characteristics.These results have a certain reference value for further analysis of the interaction between ultrafast laser and matter.