VIRTUAL NANOLAB BY QUANTUMWISE Presentation by: Sheng Yu Supervisor: Dr. Qiliang Li

Outline: 2. Example about simulation on MoS2 monolayer Build structure 1. Download and install Virtual NanoLab 2. Example about simulation on MoS2 monolayer Build structure Optimize the structure Change your unit cell Simulate your structure Analyze your results 3. Simulation on the conductance for small MoS2 nanosheet

http://www.quantumwise.com/products/download

We will replace this 14-day DEMO license by our own one-month license.

C:\Program Files (x86)\QuantumWise\atk-13.8.1\license

Next – Next – Finish

http://www.quantumwise.com/documents/manuals/latest/InstallationGuide /InstallationGuide.pdf

1. Open Virtual NanoLab

2. Build your own structure. ① Jobs command window ② The jobs you have already finished ③ The jobs you are going to analyze ④ Analysis window

2. Build your own structure.

Select right three atoms and press Delete to delete them

Press Ctrl + R:

Important!

3. Optimize your structure Go to Script Generator

Save your Job

Run it!

4. Change your unit cell but not change the structure

Press Ctrl + R:

Important!

5. Simulate your structure

6. See your simulation results!

Band structure for monolayer MoS2 Density of states for monolayer MoS2

Fermi energy level for monolayer MoS2 Electron density for monolayer MoS2

Effective mass

Effective mass Direction: [0, 1, 0]: zigzag [0, 0, 1]: armchair

7. Conductance for MoS2 nanosheet Making MoS2 nanosheet The difference between nanosheet and monolayer is nanosheet have finite width and atoms so that we can simulate its conductance.

The transmission spectrum is the first step for conductance of nanosheet.

Transmission spectrum of perfect sheets of graphene and MoS2: http://www.quantumwise.com/publications/tutorials/mini-tutorials/167 Opening a band gap in silicene and bilayer graphene with an electric field: http://www.quantumwise.com/publications/tutorials/mini-tutorials/209 Effective mass of electrons in silicon: http://www.quantumwise.com/publications/tutorials/mini-tutorials/135 Sheng Yu Email: syu12@masonlive.gmu.edu Phone number: 7036470780 Engineering Building 2602