As the trend of miniaturization continues, the next generation of electronic devices will undoubtedly be downsized to nanoscale. Numerous previous studies have convincingly shown that many exciting features of nanoscale devices are closely related to their intrinsic electronic properties that are dominated by quantum effects. Quantum modeling based on first-principle computational methods now has become a major theoretical tool in understanding electronic, magnetic and transport properties of nanoscale systems under operating conditions and also relating these properties to novel device functions.

 

Current research interests along this direction mainly include 1) the computational design of novel types of nanoscale electronic/spintronic devices using various kinds of materials and 2) providing theoretical explain for novel (and often puzzling) nanoscale transport phenomena observed in experiments. As an example for nanoscale electronic/spintronic devices we designed via computational modeling, we show below novel logic gates made of graphene nanoribbons1.

 

nano device

Fig. control of spin-polarized current in zigzag graphene nanoribbon by magnetization of leads and bias voltage. Green triangle – majority spin & parallel magnetization, pink down-triangle – minority spin & parallel magnetization, blue circle – majority spin & antiparallel magnetization, orange square – minority spin & antiparallel magnetization.

 

[1] M G Zeng et al., Appl. Phys. Lett., 98, 092110 (2011).


Selected Publications

[1] Q. Y. Wu, L. Shen, Z. Q. Bai, M. G. Zeng, M. Yang, Z. G. Huang, and Y. P. Feng, Efficient Spin Injection into Graphene through a Tunnel Barrier: Overcoming the Spin-Conductance Mismatch, Phys. Rev. Applied 2, 4 (2014).

[2] M. G. Zeng, L. Shen, H. B. Su, C. Zhang, and Y. P. Feng, Graphene-based Spin Logic Gates, Appl. Phys. Lett. 98, 9 (2011).

[3] M. G. Zeng, L. Shen, M. Zhou, C. Zhang, and Y. P. Feng, Graphene-based Bipolar Spin Diode and Spin Transistor: Rectification and Amplification of Spin-polarized Current, Phys. Rev. B 83, 11 (2011).

[4] A. Nurbawono, S. L. Liu, C. A. Nijhuis, and C. Zhang, Odd–Even Effects in Charge Transport through Self-Assembled Monolayer of Alkanethiolates, J. Phys. Chem. C 119, 10 (2015).

[5] M. Zhou, Y. Q. Cai, M. G. Zeng, C. Zhang, and Y. P. Feng, Mn-doped Thiolated Au25 Nanoclusters: Atomic Configuration, Magnetic Properties, and A Possible High-performance Spin Filter, arXiv preprint arXiv:1311.5701 (2013).

[6] A. Nurbawono, Y. P. Feng, E. H. Zhao, and C. Zhang, Differential Conductance Anomaly in Superconducting Quantum Point Contacts, Phys. Rev. B 80, 18 (2009).