Messages

1

General Questions and Answers / Monkhorst Pack-grid used in calculating transmission spectrum

« on: May 23, 2012, 06:07 »

I knew that only (ka,kb) components are used in calculating transmission spectrum
because the structure of central molecule is not periodical along kc direction.

What I haven't understood is that central molecule is usually not periodical along (ka,kb), thus can
Monkhorst Pack-grid(ka,kb) apply to calculating transmission spectrum accurately?

2

General Questions and Answers / I-V curve of DTB device

« on: May 21, 2012, 03:18 »

I redid the calculation of transmission spectrum and I-V curve illustrated in Fig2 and Fig4 in ' Comp. Mat. Sci. 27, 151 (2003) '
The parameter setting is followed by tutorial 'Molecular Devices' except for k-point sampling. I set (1,1,50) instead of (3,3,50).
As we calculated I-V curve of DTB device, our result couldn't match the result in paper at voltage higher than 4 Volt.
I guessed it due to iteration tolerance because I reduced iteration tolerance to 0.05 at higher bias. However, I didn't found
the exact problem, so I need some advises from you.
thanks you

3

General Questions and Answers / Projection on device density of state

« on: March 29, 2012, 10:03 »

Does the latest version ATK support plotting of DensityOfStates projected onto the eigenstates of the MPSH by importing pylab?
I thought DOS projected on MPSH help us understant more clearly which eigenstate contributes most to DOS and TransmissionSpectrum.
If pylab can do it, it will be very helpful.