C. Z. Wang
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
C. Z. Wang has a total of 53 co-authors. Here are the top co-authors by number of shared publications:
- Kai Ming Ho
Ames Laboratory, US Department of Energy, Ames, Iowa 50011, USA
25 shared publications - Che Ting Chan
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
6 shared publications G. Kopidakis
Department of Materials Science and Technology, University of Crete, P.O. Box 2208, 71003 Heraklion, Crete, Greece
3 shared publicationsB. J. Min
Ames Laboratory–U.S. Department of Energy and Department of Physics, Iowa State University, Ames, Iowa 50011
2 shared publicationsLi-Zhen Zhao
College of Physics and Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, Qingdao University, Qingdao, Shandong 266071, PR China
2 shared publicationsW. C. Lu
Ames Laboratory–U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
2 shared publications
Latest Publications
- 1 January 2018
- Published by Optica Publishing Group
- p. FM1F.6
Optically Induced Correlated Phase in CaKFe4As4 Superconductor
Ultrafast correlation phenomena is studied on a newly discovered, 1144-type superconductor CaKFe4As4 for the first time. Broadband spectral-temporal visualization follows distinct pair breaking processes and reveal, strikingly, the build-up of a hidden correlated quasiparticle phase with an estimated gap of ~10 meV.
- 1 January 2018
- Published by Optica Publishing Group
- p. FM1F.6
Optically Induced Correlated Phase in CaKFe4As4 Superconductor
Ultrafast correlation phenomena is studied on a newly discovered, 1144-type superconductor CaKFe4As4 for the first time. Broadband spectral-temporal visualization follows distinct pair breaking processes and reveal, strikingly, the build-up of a hidden correlated quasiparticle phase with an estimated gap of ~10 meV.
- 23 January 2014
- Published by American Physical Society (APS) in Physical Review B
- Vol. 89 (4) , 045131
Correlation matrix renormalization approximation for total-energy calculations of correlated electron systems
We generalized the commonly used Gutzwiller approximation for calculating the electronic structure and total energy of strongly correlated electron systems. In our method, the evaluation of one-body and two-body density matrix elements of the Hamiltonian is simplified using a renormalization approximation to achieve better scaling of the computational effort as a function of system size. To achieve a clear presentation of the concept and methodology, we describe the detailed formalism for a finite hydrogen system with minimal basis set. We applied the correlation matrix renormalization approximation approach to a H dimer and H cubic fragment with minimal basis sets, as well as a H molecule with a large basis set. The results compare favorably with sophisticated quantum chemical calculations. We believe our approach can serve as an alternative way to build up the exchange-correlation energy functional for an improved density functional theory description of systems with strong electron correlations.- 23 January 2014
- Published by American Physical Society (APS) in Physical Review B
- Vol. 89 (4) , 045131
Correlation matrix renormalization approximation for total-energy calculations of correlated electron systems
We generalized the commonly used Gutzwiller approximation for calculating the electronic structure and total energy of strongly correlated electron systems. In our method, the evaluation of one-body and two-body density matrix elements of the Hamiltonian is simplified using a renormalization approximation to achieve better scaling of the computational effort as a function of system size. To achieve a clear presentation of the concept and methodology, we describe the detailed formalism for a finite hydrogen system with minimal basis set. We applied the correlation matrix renormalization approximation approach to a H dimer and H cubic fragment with minimal basis sets, as well as a H molecule with a large basis set. The results compare favorably with sophisticated quantum chemical calculations. We believe our approach can serve as an alternative way to build up the exchange-correlation energy functional for an improved density functional theory description of systems with strong electron correlations.- Open Access
- 23 February 2012
- Published by Wiley in International Journal of Quantum Chemistry
- Vol. 112 (15) , 2766
The benchmark of gutzwiller density functional theory in hydrogen systems
- 23 February 2012
- Published by Wiley in International Journal of Quantum Chemistry
- Vol. 112 (15) , 2766
Open AccessThe benchmark of gutzwiller density functional theory in hydrogen systems
- 30 August 2011
- Published by Wiley in International Journal of Quantum Chemistry
- Vol. 112 (1) , 240-246
The benchmark of Gutzwiller density functional theory in hydrogen systems
- 30 August 2011
- Published by Wiley in International Journal of Quantum Chemistry
- Vol. 112 (1) , 240-246
The benchmark of Gutzwiller density functional theory in hydrogen systems
- 16 May 2011
- Published by American Physical Society (APS) in Physical Review B
- Vol. 83 (18) , 184103
Structure and dynamics of liquid NiZrbyab initiomolecular dynamicsFirst-principles molecular dynamics simulations are performed to investigate the interplay between the local structure and atomic dynamics of liquid NiZr eutectic alloy in the equilibrium and undercooled states. The topological and chemical short-range orders (SROs) as characterized by the partial pair-correlation functions show good agreement with recent neutron-scattering experiments. Three-dimensional structural analysis shows that the local environment around both Ni and Zr atoms is more complex than the icosahedral SRO due to the frustration of icosahedra driven by the strong directional interaction and large size difference between Ni and Zr. The atomic dynamics analysis shows that the Ni-centered and Zr-centered Voronoi polyhedra with relatively longer lifetime play a key role in slowing down the dynamics. The fraction of these clusters increases significantly as the liquid is cooled down and thus facilitates glass formation in the rapidly quenched alloys.- 16 May 2011
- Published by American Physical Society (APS) in Physical Review B
- Vol. 83 (18) , 184103
Structure and dynamics of liquid NiZrbyab initiomolecular dynamicsFirst-principles molecular dynamics simulations are performed to investigate the interplay between the local structure and atomic dynamics of liquid NiZr eutectic alloy in the equilibrium and undercooled states. The topological and chemical short-range orders (SROs) as characterized by the partial pair-correlation functions show good agreement with recent neutron-scattering experiments. Three-dimensional structural analysis shows that the local environment around both Ni and Zr atoms is more complex than the icosahedral SRO due to the frustration of icosahedra driven by the strong directional interaction and large size difference between Ni and Zr. The atomic dynamics analysis shows that the Ni-centered and Zr-centered Voronoi polyhedra with relatively longer lifetime play a key role in slowing down the dynamics. The fraction of these clusters increases significantly as the liquid is cooled down and thus facilitates glass formation in the rapidly quenched alloys.- 28 February 2011
- Published by Elsevier in Computational and Theoretical Chemistry
- Vol. 963 (2-3) , 439-447
Carbon-rich C9Sin (n=1–5) clusters from ab initio calculations
- 28 February 2011
- Published by Elsevier in Computational and Theoretical Chemistry
- Vol. 963 (2-3) , 439-447
Carbon-rich C9Sin (n=1–5) clusters from ab initio calculations
- 15 December 2010
- Published by Wiley in Journal of Computational Chemistry
- Vol. 32 (7) , 1271-1278
Competitive diamond-like and endohedral fullerene structures of Si70
- 15 December 2010
- Published by Wiley in Journal of Computational Chemistry
- Vol. 32 (7) , 1271-1278
Competitive diamond-like and endohedral fullerene structures of Si70
- 12 May 2010
- Published by American Physical Society (APS) in Physical Review B
- Vol. 81 (19) , 195419
Reconstruction and evaporation at graphene nanoribbon edges
The reconstruction and evaporation at graphene nanoribbon (GNR) edges are investigated by tight-binding molecular-dynamics simulations and ab initio calculations. It is observed that reconstruction through the formation of pentagon-heptagon pairs can take place quickly along the zigzag edge and it is energetically favorable. At very high temperatures, the armchair edge is found to change into a zigzag edge structure, which further accelerates the evaporation of carbon atoms and leads to the formation of carbon linear chains. The evaporation of carbon atoms from both the zigzag and armchair edges is preceded by the formation of heptagon rings, which serve as a gateway for carbon atoms to escape. In the simulation for a GNR armchair-zigzag-armchair junction, carbon atoms are evaporated row by row from the outermost row of the zigzag edge while the armchair edge remains nearly intact. These results can be applied to nanoelectronic devices fabrication through the temperature-controlled edge structure of GNR.
- 12 May 2010
- Published by American Physical Society (APS) in Physical Review B
- Vol. 81 (19) , 195419
Reconstruction and evaporation at graphene nanoribbon edges
The reconstruction and evaporation at graphene nanoribbon (GNR) edges are investigated by tight-binding molecular-dynamics simulations and ab initio calculations. It is observed that reconstruction through the formation of pentagon-heptagon pairs can take place quickly along the zigzag edge and it is energetically favorable. At very high temperatures, the armchair edge is found to change into a zigzag edge structure, which further accelerates the evaporation of carbon atoms and leads to the formation of carbon linear chains. The evaporation of carbon atoms from both the zigzag and armchair edges is preceded by the formation of heptagon rings, which serve as a gateway for carbon atoms to escape. In the simulation for a GNR armchair-zigzag-armchair junction, carbon atoms are evaporated row by row from the outermost row of the zigzag edge while the armchair edge remains nearly intact. These results can be applied to nanoelectronic devices fabrication through the temperature-controlled edge structure of GNR.
- 7 July 2009
- Published by American Physical Society (APS) in Physical Review B
- Vol. 80 (4) , 045307
Interfacial disorder and optoelectronic properties of diamond nanocrystals
We present in this work a theoretical framework based on the tight-binding method, which is able to probe at a local atomic level the optoelectronic response of nanomaterial systems and link it to the associated disorder. We apply this methodology to carbon nanocomposites containing diamond nanocrystals. We find that significant structural and topological disorder exists at the interface between the nanodiamonds and the embedding amorphous carbon matrix. This can be quantitatively probed by extracting the Urbach energies from the optical parameters. Disorder in the nanocrystals appears in their outer shell near the interface and is manifested as bond length and angle distortions. Energetics and stability analysis show that nanodiamonds embedded in matrices with high density and high fraction of fourfold coordinated atoms are more stable.
- 7 July 2009
- Published by American Physical Society (APS) in Physical Review B
- Vol. 80 (4) , 045307
Interfacial disorder and optoelectronic properties of diamond nanocrystals
We present in this work a theoretical framework based on the tight-binding method, which is able to probe at a local atomic level the optoelectronic response of nanomaterial systems and link it to the associated disorder. We apply this methodology to carbon nanocomposites containing diamond nanocrystals. We find that significant structural and topological disorder exists at the interface between the nanodiamonds and the embedding amorphous carbon matrix. This can be quantitatively probed by extracting the Urbach energies from the optical parameters. Disorder in the nanocrystals appears in their outer shell near the interface and is manifested as bond length and angle distortions. Energetics and stability analysis show that nanodiamonds embedded in matrices with high density and high fraction of fourfold coordinated atoms are more stable.
- 16 March 2009
- Published by American Physical Society (APS) in Physical Review B
- Vol. 79 (11) , 113404
Competition between area and height evolution of Pb islands on a Si(111) surface
Scanning tunneling microscopy experiments reveal that small Pb islands with unstable heights, e.g., four layers, on a Si(111) surface decay during coarsening, whereas large islands do not decay but grow to a stable height. This bifurcation in evolution is analyzed by incorporating quantum size effects into theoretical models for island growth dynamics with appropriate geometries. The effective energy barrier for Pb atoms to reach the top of four-layer islands is estimated at about 0.26 eV.
- 16 March 2009
- Published by American Physical Society (APS) in Physical Review B
- Vol. 79 (11) , 113404
Competition between area and height evolution of Pb islands on a Si(111) surface
Scanning tunneling microscopy experiments reveal that small Pb islands with unstable heights, e.g., four layers, on a Si(111) surface decay during coarsening, whereas large islands do not decay but grow to a stable height. This bifurcation in evolution is analyzed by incorporating quantum size effects into theoretical models for island growth dynamics with appropriate geometries. The effective energy barrier for Pb atoms to reach the top of four-layer islands is estimated at about 0.26 eV.