Example #1
0
def excite_system(mesh, time=5, snaps=501):

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

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

    # Load the initial state from the npy file saved
    # in the realxation
    sim.set_m(np.load('m0.npy'))

    # Add the 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 x ns and save
    # 'snaps' snapshots of the system in the process
    ts = np.linspace(0, time * 1e-9, snaps)

    for t in ts:
        print 'time', t
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
Example #2
0
def excite_system(mesh, time=5, snaps=501):

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

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

    # Load the initial state from the npy file saved
    # in the realxation
    sim.set_m(np.load('m0.npy'))

    # Add the 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 x ns and save
    # 'snaps' snapshots of the system in the process
    ts = np.linspace(0, time * 1e-9, snaps)

    for t in ts:
        print('time', t)
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
Example #3
0
def excite_system(mesh):
    sim = Sim(mesh, name='dyn', driver='llg_stt')
    sim.set_tols(rtol=1e-8, atol=1e-10)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5

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

    exch = UniformExchange(A=1.3e-11)
    sim.add(exch)
    dmi = DMI(D=-4e-3)
    sim.add(dmi)
    zeeman = Zeeman((0, 0, 4e5))
    sim.add(zeeman, save_field=True)

    sim.jx = -5e12
    sim.beta = 0

    ts = np.linspace(0, 0.5e-9, 101)
    for t in ts:
        print 'time', t
        sim.run_until(t)
        sim.save_vtk()
Example #4
0
def excite_system(mesh):
    sim = Sim(mesh, name='dyn', driver='llg_stt')
    sim.set_tols(rtol=1e-8, atol=1e-10)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5

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

    exch = UniformExchange(A=1.3e-11)
    sim.add(exch)
    dmi = DMI(D=-4e-3)
    sim.add(dmi)
    zeeman = Zeeman((0, 0, 4e5))
    sim.add(zeeman, save_field=True)

    sim.jx = -5e12
    sim.beta = 0

    ts = np.linspace(0, 0.5e-9, 101)
    for t in ts:
        print 'time', t
        sim.run_until(t)
        sim.save_vtk()