Messages

1

General Questions and Answers / ValueError: No name (no name) Error Killing Simulation

« on: May 6, 2021, 19:45 »

Hello,

When I run the atkpython command on my script to add new bias points for IVCharacteristics to my converged 0-bias result, I get the following error:

Traceback (most recent call last):
  File "pmos_3p5L_0p7T_with_barriers_v2.py", line 667, in <module>
    enforce_zero_transmission_in_band_gap=True,
  File "zipdir/NL/Study/IVCharacteristics.py", line 1889, in __init__
  File "zipdir/NL/Study/Study.py", line 532, in _saveState
  File "zipdir/NL/Study/Study.py", line 517, in _saveToFile
  File "zipdir/NL/IO/NLSaveUtilities.py", line 471, in nlsave
  File "zipdir/NL/IO/HDF5.py", line 279, in __delitem__
  File "h5py/_objects.pyx", line 54, in h5py._objects.with_phil.wrapper
  File "h5py/_objects.pyx", line 55, in h5py._objects.with_phil.wrapper
  File "build/lib/python3.6/site-packages/h5py-2.7.1-py3.6-linux-x86_64.egg/h5py/_hl/group.py", line 167, in __getitem__
  File "h5py/_objects.pyx", line 54, in h5py._objects.with_phil.wrapper
  File "h5py/_objects.pyx", line 55, in h5py._objects.with_phil.wrapper
  File "h5py/h5o.pyx", line 190, in h5py.h5o.open
ValueError: No name (no name)
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0

I am using the Q-2019.12 version. My initial result converged using this version, so I am still using this version as changing versions means that I need to perform the 0-bias calculation again.

I also tried performing the nldelete() command to remove the last DeviceConfiguration as I suspected that there must have been a problem when saving the last configuration into the hdf5 file. Doing so also gives the ValueError: No name (no name) error.

Any help would be much appreciated.

2

General Questions and Answers / Re: Error when starting the QATK scriptor from builder

« on: May 6, 2021, 19:32 »

Dear Mlee,

I have solved the error by reseting the

C:\Users\[username]\.vnl
C:\Users\[username]\.quantumwise

Thanks

What do you mean by resetting?

Thanks.

3

General Questions and Answers / Re: Energy level splitting in Projected DOS

« on: September 16, 2020, 23:21 »

Thank you for your reply, Tue.

On the y-axis is energy in eV.

I've attached examples of energy levels I've observed in the DoS. Note how there are clear energy levels in the central region which coincides with the gate region. In the plot in my original post, I plotted the energies at which these levels appear.

4

General Questions and Answers / Re: Energy level splitting in Projected DOS

« on: September 14, 2020, 20:25 »

Pls help!!

5

General Questions and Answers / Energy level splitting in Projected DOS

« on: September 2, 2020, 19:50 »

Hello,

Using the ATK-DFT (NEGF) solver of QuantumATK, I am observing a weird splitting of energy levels in the projected DOS of my device. I have simulated my NMOS nanowire down to 5 K and have plotted the energy levels that appear in the gate region of the projected DoS as a function of gate voltage with Vds = 1 mV (attached to this post).

As can be seen, the energy levels change with temperature, experiencing a large splitting at colder temperatures.

Is there a physical interpretation of this splitting? I know it can't be Coulomb Blockade as the NEGF formalism used in QuantumATK describes a time-independent electronic distribution in the steady state.