We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linea...We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linear medium) and Stark effects. It is observed that the Stark and Kerr effects play a prominent role during the time evolution of the quantum system. The evolving quantum Fisher information (QFI) is noted as time grows under the non-linear Kerr medium contrary to the QE for higher dimensional systems. The effect of non-linear Kerr medium is greater on the QE as we increase the value of Kerr parameter. However, QFI and QE maintain their periodic nature under atomic motion. On the other hand, linear Kerr medium has no prominent effects on the dynamics of N-level atomic system. Furthermore, it has been observed that QFI and QE decay soon under the influence of Stark effect. In short, the N-level atomic system is found prone to the change of the Kerr medium and Stark effect for higher dimensional systems.展开更多
In this paper,the authors propose a new space vector pulse width modulation(SVPWM)algorithm based on non-orthogonal coordinates for N-level inverters.First,it is pointed out that classicalαβcoordinates-based SVPWM h...In this paper,the authors propose a new space vector pulse width modulation(SVPWM)algorithm based on non-orthogonal coordinates for N-level inverters.First,it is pointed out that classicalαβcoordinates-based SVPWM has many shortcomings because of improper coordinate choice.Then,a non-orthogonal coordinates-based SVPWM is proposed to solve these problems.The proposed algorithm can easily identify which sector the reference space vector falls in and conduct simple operations to find the duty cycle of each vector.Finally,it is verified that the proposed SVPWM is actually a pulse−width modulation(PWM)technology based on line voltages.展开更多
文摘We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linear medium) and Stark effects. It is observed that the Stark and Kerr effects play a prominent role during the time evolution of the quantum system. The evolving quantum Fisher information (QFI) is noted as time grows under the non-linear Kerr medium contrary to the QE for higher dimensional systems. The effect of non-linear Kerr medium is greater on the QE as we increase the value of Kerr parameter. However, QFI and QE maintain their periodic nature under atomic motion. On the other hand, linear Kerr medium has no prominent effects on the dynamics of N-level atomic system. Furthermore, it has been observed that QFI and QE decay soon under the influence of Stark effect. In short, the N-level atomic system is found prone to the change of the Kerr medium and Stark effect for higher dimensional systems.
文摘In this paper,the authors propose a new space vector pulse width modulation(SVPWM)algorithm based on non-orthogonal coordinates for N-level inverters.First,it is pointed out that classicalαβcoordinates-based SVPWM has many shortcomings because of improper coordinate choice.Then,a non-orthogonal coordinates-based SVPWM is proposed to solve these problems.The proposed algorithm can easily identify which sector the reference space vector falls in and conduct simple operations to find the duty cycle of each vector.Finally,it is verified that the proposed SVPWM is actually a pulse−width modulation(PWM)technology based on line voltages.