4.1.7. Parameters for time-evolution

  • dt

    Type : Positive Double(Default value : 0.1)

    Description : The width of time steps.

  • PumpType

    Type : String (Chosen from "Quench", "Pulse Laser", "AC Laser", and "DC Laser".Default value : "Quench")

    Description : The type of time-dependent Hamiltonian. For "Quench", two body operator \(U_{\rm quench} \sum_i n_{i \uparrow} n_{i \downarrow}\) is added. For "Pulse Laser", "AC Laser", and "DC Laser", the hopping term is modulated as \(-\sum_{i j \sigma} t_{i j} \exp[-{\bf A}(t) \cdot ({\bf R}_i-{\bf R}_j)/(2\pi)] c^\dagger_{i \sigma} c_{j \sigma}\), where \({\bf A}(t)\) is the vector potential which is defined as \({\bf A}(t) = {\bf A}_0 \exp[-(t-t_0)^2/(2 t_{\rm dump}^2)] \cos[\omega (t-t_0)]\), \({\bf A}(t) = {\bf A}_0 \sin[\omega (t-t_0)]\), and \({\bf A}(t) = {\bf A}_0 t\) for for "Pulse Laser", "AC Laser", and "DC Laser", respectively.

    potential.dat file is written for displaying the vector potential and the electrical field at each time step.

  • Uquench

    Type : Double(Default value : 0.0)

    Description : \(U_{\rm quench}\)

  • freq

    Type : Double(Default value : 0.1)

    Description : \(\omega\)

  • tshift

    Type : Double(Default value : 0.0)

    Description : \(t_0\)

  • tdump

    Type : Double (Default value : 0.1)

    Description : \(t_{\rm dump}\)

  • VecPotW, VecPotL

    Type : Double (Default value : 0.0)

    Description : The vector potential (fractional coordinate of the reciprocal space) at \(t=t_0\). The reciprocal lattice vector is computed from the direct lattice vector shown in Fig. 4.1 , Fig. 4.2 , Fig. 4.3, Fig. 4.4 .