how to calculate alignment of magnetic moment in electrode in two probe geometry

[sweta]

Hello all,

In two probe geometry how I can calculate the transport dependence on the alignment of magnetic moments in the Ni electrodes?

Please help!

Regards,
Sweta

[Jess Wellendorff]

Sounds like you need to modify the atomic magnetization directions in the Ni electrodes. Use the "Initial State" block for this. See an example here: https://docs.quantumwise.com/tutorials/fe_mgo_fe/fe_mgo_fe.html#anti-parallel-spin

[sweta]

Thank You Jess.

I have calculated transmission spectra for parallel spin and getting the result attached herewith. I want to know in this spectra, is the black color spectra show spin up results and red color shows spin down results?

One more thing is that after calculating this spectra I run the script shown below to calculate the I-V curve. The calculated I-V shows sum current. But I want to calculate spin up and spin down current separately. How I can do this?  what script I should use so that I will get spin up and spin down current ?

#read in the 0 V configuration
device_configuration = nlread("Ni_parallel.nc",DeviceConfiguration)[0]
calculator = device_configuration.calculator()

# Define bias voltages
voltage_list=[0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, -1.4, -1.6, -1.8, -2.0]*Volt
#make loop
for voltage in voltage_list:
    # Set new calculator with modified electrode voltages on the configuration
    # use the self consistent state of the old calculation as starting input.
    device_configuration.setCalculator(
          calculator(electrode_voltages=(-0.5*voltage, 0.5*voltage)),
          initial_state=device_configuration)
         
    # Calculate the transmission spectrum
    transmission_spectrum = TransmissionSpectrum(
        configuration=device_configuration,
        energies=numpy.linspace(-4,4,101)*eV,
        kpoints=MonkhorstPackGrid(1,1),
        )
       
    #save the results
    nlsave('Ni_parallel.nc', device_configuration)
    nlsave('Ni_parallel.nc', transmission_spectrum)

[Petr Khomyakov]

In the VNL, you can always choose which curves ('Curves') to be shown on the graph, see https://docs.quantumwise.com/tutorials/fe_mgo_fe/fe_mgo_fe.html.