示例#1
0
文件: main.py 项目: fangohr/fidimag
def excite_system(mesh):

    # Specify the stt dynamics in the simulation
    sim = Sim(mesh, name='dyn', driver='llg_stt')

    sim.set_tols(rtol=1e-12, atol=1e-14)
    sim.alpha = 0.05
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5

    # sim.set_m(init_m)
    sim.set_m(np.load('m0.npy'))

    # Energies
    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    anis = UniaxialAnisotropy(5e4)
    sim.add(anis)

    # dmi = DMI(D=8e-4)
    # sim.add(dmi)

    # Set the current in the x direction, in A / m
    # beta is the parameter in the STT torque
    sim.jx = -1e12
    sim.beta = 1

    # The simulation will run for 5 ns and save
    # 500 snapshots of the system in the process
    ts = np.linspace(0, 5e-9, 501)

    for t in ts:
        print 'time', t
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
示例#2
0
文件: main.py 项目: fangohr/fidimag
def excite_system(mesh):

    # Specify the stt dynamics in the simulation
    sim = Sim(mesh, name='dyn', driver='llg_stt')

    sim.set_tols(rtol=1e-12, atol=1e-14)
    sim.alpha = 0.05
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5

    # sim.set_m(init_m)
    sim.set_m(np.load('m0.npy'))

    # Energies
    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    anis = UniaxialAnisotropy(5e4)
    sim.add(anis)

    # dmi = DMI(D=8e-4)
    # sim.add(dmi)

    # Set the current in the x direction, in A / m
    # beta is the parameter in the STT torque
    sim.jx = -1e12
    sim.beta = 1

    # The simulation will run for 5 ns and save
    # 500 snapshots of the system in the process
    ts = np.linspace(0, 5e-9, 501)

    for t in ts:
        print 'time', t
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
示例#3
0
文件: main.py 项目: River315/fidimag
def excite_system(mesh):

    sim = Sim(mesh, name='dyn')

    sim.set_tols(rtol=1e-10, atol=1e-14)
    sim.alpha = 0.01
    sim.gamma = 2.211e5
    sim.Ms = spatial_Ms

    # sim.set_m(init_m)
    sim.set_m(np.load('m0.npy'))

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    demag = Demag()
    sim.add(demag)

    mT = 795.7747154594767
    sigma = 0.08e-9

    def gaussian_fun(t):

        return np.exp(-0.5 * (t / sigma)**2)

    zeeman = TimeZeeman((80 * mT, 0, 0), time_fun=gaussian_fun, name='hx')
    #zeeman = Zeeman((100*mT,0,0), name='hx')
    sim.add(zeeman, save_field=True)

    ts = np.linspace(0, 1e-9, 501)

    for t in ts:
        print 'time', t
        print 'length:', sim.spin_length()[0:200]
        sim.run_until(t)
        sim.save_vtk()
示例#4
0
文件: main.py 项目: takluyver/fidimag
def excite_system(mesh):

    sim = Sim(mesh, name='dyn')

    sim.set_tols(rtol=1e-10, atol=1e-14)
    sim.alpha = 0.01
    sim.gamma = 2.211e5
    sim.Ms = spatial_Ms

    # sim.set_m(init_m)
    sim.set_m(np.load('m0.npy'))

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    demag = Demag()
    sim.add(demag)

    mT = 795.7747154594767
    sigma = 0.08e-9

    def gaussian_fun(t):

        return np.exp(-0.5 * (t / sigma)**2)

    zeeman = TimeZeeman((80 * mT, 0, 0), time_fun=gaussian_fun, name='hx')
    #zeeman = Zeeman((100*mT,0,0), name='hx')
    sim.add(zeeman, save_field=True)

    ts = np.linspace(0, 1e-9, 501)

    for t in ts:
        print 'time', t
        print 'length:', sim.spin_length()[0:200]
        sim.run_until(t)
        sim.save_vtk()