The Condensed Matter Theory (CMT) Group at Tunghai University is the essential group in researching theoretical condensed matter physics with both analytical and numerical methods. Basically, the targets of investigation are various lattice models.

Since several main algorithms in lattice systems are emploied and the computational resources are abundant, numerical study expecially has become the feature of the group. The members are proficient in Variational and Quantum Monte Carlo simulations, Exact Diagonalization, and Density Matrix Renormalization Group. On the other hand, almost 200 high performance PCs are built into lots of PC-Clusters for parallel computing.

The research interests of the professors cover diverse subareas. A regular seminar takes place on each Thursday on the topics of high temperature superconductivity, quantum Hall effect, strongly correlated systems, ultra-cold atoms, soft condensed matters, and supersolid phases. Speakers are invited from other universities in Taiwan or from other countries. Moreover, the members of the group also introduce their recent works respectively. Sometimes an internet convention is held with Academic Sinica, National Taiwan University, and National Tsing Hua University; therefore projects are collaborated frequently with other outstanding scholars. The CMT Group is the main theoretical team which plays an important role in the Department of Physics at Tunghai University. Most of theoretical publications of the department of physics were reported by the CMT Group.

Students who desire further study are welcome to contact the faculty directly.

Center for High Performance Computing: Location: ST126, Phone: +886-4-23590121 ext 32107

Theoretical physics discussion group: Your e-mail subscriptions are welcome!

- Faculty
- Yung-Chung Chen
- Ph.D in Physics,Sep. 1984 - Jun. 1988, National Tsing Hua Univ. (Taiwan)
- B.S. in ElectroPhysics, Sep. 1980 - Jun. 1984, National Chiao Tung Univ. (Taiwan)
- Prof. Yung-Chung Chen is interested in all aspects about correlation effects in quantum many-body problems. In the past few years, he has been working on the following subjects:
- Numerical study of the strongly correlated system such as Hubbard Model, t-J Model, and Frustrated Spin Model.
- Mean field theory and quantum Monte Carlo simulation of the quantum spin systems.
- Development of new numerical methods for strongy correlated systems, such as the Power-Lanczos Method.
- Min-Fong Yang
- Ph.D in Physics, 1992, National Tsing Hua Univ. (Taiwan)
- B.S. in ElectroPhysics, 1987, National Chiao Tung Univ. (Taiwan)
- Prof. Min-Fong Yang is interested in heavy fermion systems,high-T
_{c}superconductivity, and quantum Hall effect. Recently he also pitched in researching and developing new numerical algorithms such as Tensor Renormalization Group. - Chi-Tin Shih
- Ph.D in Physics, 1991-1997, National Tsing Hua Univ. (Taiwan)
- B.S. in Physics, 1986-1990, National Tsing Hua Univ. (Taiwan)
- Prof. Chi-Tin Shih's research interests are theory of high-temperature superconductivity, Strongly correlated
electron systems, Structure and transport of bio-macromolecules,and High-performance computing and its
application on physics. He came off with flying colors in researching extended t-J model,a model describes
high-T
_{c}superconductor,and awarded prizes of Academia Sinica and National Center for Theoretical Scinences in 2007. Furthermore, Prof. Chi-Tin Shih applies tight binding model to describe the properties of electronic transport in DNA. The impact of prof. Shih's work is expected longer and wider. - Yu-Wen Lee
- Ph.D in Physics, 1996-2000, National Tsing Hua Univ. (Taiwan)
- M.S. in Physics, 1991-1993, National Taiwan Univ. (Taiwan)
- B.S. in Electrical Engineering, 1987-1991, National Taiwan Univ. (Taiwan)
- Prof. Yu-Wen Lee is intersted in
- Phases and phase transitions of quantum magnets
- Transport in low-dimensional systems. Kondo effect and Luttinger liquid
- Many-body physics of cold atoms
- Applications of quantum field theory
- Kwai-Kong Ng
- Ph.D in Physics, 1993-1998, University of Cincinnati, Cincinnati OH, USA
- M.S. in Physics, 1991-1993, Hong Kong University of Science and Technology. (Hong Kong)
- B.S. in Physics, 1988-1991, University of Hong Kong. (Hong Kong)
- Prof. Ng's research interest is Strongly correlated quantum many-particle systems, Numerical simulation methods in quantum physics, Quantum phase transitions, and most recently on the numerical study of the supersolid phase in various lattice models.

- Postdoctoral Fellowship

**Research Personnel:**

- Research Assistant
- Jianiue Chen
- BSc in Physics, 2007, Tunghai Univ.(Taiwan)

- Former Research Assistant
- Jian Jheng Wu
- Yun-Yin Cheng
- M.S. in Physics, 2009, Tunghai Univ.(Taiwan)

- Technical Advisors
- Yu-Chin Tzeng
- BSc in Physics, 2005, Tunghai Univ.(Taiwan)
- Military service, 2005 - 2006
- Research Assistant, 2007 - July 2009, Dep. Physics, Tunghai Univ.(Taiwan)
- MSc in Physics, 2011, National Tsing Hua Univ.(Taiwan)
- phD student, 2011 - 2013, National Taiwan Univ.
- phD student, 2013 - now, National Taiwan Univ.
- parity quantum numbers in the DMRG, Phys. Rev. B
**86**, 024403 (2012) - Chia-hei Yang
- Adjunct Assistant Professor, July 2012-Feb. 2013, Photonic, Feng-Chia Univ., Taiwan
- Adjunct Assistant Professor, Feb. 2011-Feb. 2013, Physics, Chinese Culture Univ., Taiwan
- Postdoctoral Researcher, 2010-2011, Physics, Academia Sinica, Taiwan
- Postdoctoral Researcher, 2007-2010, Physics, Tunghai Univ., Taiwan
- Ph.D in Physics, 2007, Univ. of California at Riverside, CA, USA

__Yu-Wen Lee__and Yu-Li Lee,*Tunneling between the topological superconductor and Luttinger liquid*,arXiv: 1401.4228.- Yu-Li Lee and
__Yu-Wen Lee__,*Electrically tunable two-channel Kondo fixed points in helical liquids*,Phys. Rev. B**88**, 035112 (2013). __Yu-Wen Lee__,__Yung-Chung Chen__, and__Min-Fong Yang__,*Stability of three-sublattice order in S=1 bilinear-biquadratic Heisenberg Model on anisotropic triangular lattices*, J. Phys. Soc. Jpn.**82**, 034705 (2013).__Yu-Wen Lee__, Yu-Li Lee, and Chung-Hou Chung,*Nonequilibrium noise correlations in a point contact of helical edge states*, Phys. Rev. B**86**, 235121 (2012).__Chi-Tin Shih__, Stephen A. Wells, Ching-Ling Hsu,__Yun-Yin Cheng__, and Rudolf A. Roemer,*The interplay of mutations and electronic properties in disease-related genes*, Scientific Reports**2**, 272 (2012).__Yu-Wen Lee__and__Min-Fong Yang__,*Spontaneous dimerization in the spin-1 bilinear-biquadratic Heisenberg model on a honeycomb lattice*, Phys. Rev. B**85**, 100402(R) (2012).- Yu-Li Lee and
__Yu-Wen Lee__,*The stability of the low-dimensional mixtures of dilute quantum gases*, J. Phys. Soc. Jpn.**80**, 044003 (2011). - A-S Chiang, C-Y Lin, C-C Chuang, H-M Chang, C-H Hsieh, C-W Yeh,
__C-T Shih__, J-J Wu, G-T Wang, Y-C Chen, C-C Wu, G-Y Chen, Y-T Ching, P-C Lee, C-Y Lin, H-H Lin, C-C Wu, H-W Hsu, Y-A Huang, J-Y Chen, H-J Chiang, C-F Lu, R-F Ni, C-Y Yeh, and J-K Hwang,*Three-Dimensional Reconstruction of Brain-wide Wiring Networks in Drosophila at Single-Cell Resolution*, Current Biology**21**, 1 (2011). __Yung-Chung Chen__,__Kwai-Kong Ng__, and__Min-Fong Yang__,*Quantum phase transitions in attractive extended Bose-Hubbard Model with three-body constraint*, Phys. Rev. B**84**, 092503 (2011).__Kwai-Kong Ng__and__Min-Fong Yang__,*Thermal Phase transitions in attractive extended Bose-Hubbard Model with three-body constraint*, Phys. Rev. B**83**, 100511(R) (2011).__Chi-Tin Shih__, Hsuan-Wen Lin, and Ann-Shyn Chiang,*Statistical analysis and modeling of the temperature-dependent sleep behavior of drosophila*, Computer Physics Communications**182**, 195 (2011).- Chia-Hei Yang, Ching-Ling Hsu, Nan-Yow Chen, and
__Chi-Tin Shih__,*Temporal dynamics of site percolation in nanoparticle assemblies*, Computer Physics Communications**182**, 71 (2011). __Chi-Tin Shih__,__Yun-Yin Cheng__, Stephen A. Wells, Ching-Ling Hsu, and Rudolf A. Romer,*Charge transport in cancer-related genes and early carcinogenesis*, Computer Physics Communications**182**, 36 (2011).__Kwai-Kong Ng__,*Thermal phase transitions of supersolids in the extended Bose-Hubbard model*, Phys. Rev. B**82**, 184505 (2010).- Pochung Chen and
__Min-Fong Yang__,*Quantum phase transitions of two-species bosons in square lattice*, Phys. Rev. B**82**, 180510(R) (2010). __Yu-Wen Lee__and__Min-Fong Yang__,*Superfluid-Insulator Transitions in Attractive Bose-Hubbard Model with Three-Body Constraint*, Phys. Rev. A**81**, 061604(R) (2010)- Yu-Li Lee and
__Yu-Wen Lee__,*Universality and stability for a dilute Bose gas with a Feshbach resonance*, Phys. Rev. A**81**, 063613 (2010). __Kwai-Kong Ng__,__Yung-Chung Chen__, and__Yu-Chin Tzeng__,*Quarter-filled supersolid and solid phases in the extended Bose-Hubbard model*, Journal of Physics: Condensed matter**22**, 185601, (2010).__Kwai-Kong Ng__,*Phase diagrams of XXZ model on depleted square lattice*, Phys. Rev. B**81**, 094426 (2010).- Pochung Chen, Chen-Yen Lai, and
__Min-Fong Yang__,*Field Induced Spin Supersolidity in Frustrated Spin-1/2 Spin-Dimer Models*, Phys. Rev. B**81**, 020409(R) (2010). - Pochung Chen, Chen-Yen Lai, and
__Min-Fong Yang__,*Numerical Study of Spin-1/2 XXZ Model on Square Lattice from Tensor Product States*, J. Stat. Mech.: Theory Exp. (2009) P10001. - Ming-Che Chang and
__Min-Fong Yang__,*Optical signature of topological insulators*, Phys. Rev. B**80**, 113304 (2009). - S. Wells,
__Chi-Tin Shih__, and Rudolf A. Romer,*Modeling Charge Transport in DNA Using Transfer Matrices with Diagonal Terms*, Int. J. Mod. Phys. B.**23**, 4138 (2009). - Ming-Che Chang and
__Min-Fong Yang__,*Magnetization plateau of the classical Ising model on the Shastry-Sutherland lattice: A tensor renormalization-group approach*, Phys. Rev. B**79**, 104411 (2009). - Sergei V. Isakov, Hong-Chi Chien, Jian-Jheng Wu,
__Yung-Chung Chen__, Chung-Hou Chung, Krishnendu Sengupta, Yong Baek Kim,*Commensurate lock-in and incommensurate supersolid phases of hardcore bosons on anisotropic triangular lattices*, Europhys. Lett.**87**, 36002 (2009) __Yu-Chin Tzeng__, Hsiang-Hsuan Hung,__Yung-Chung Chen__,__Min-Fong Yang__,*Fidelity approach to Gaussian transitions*, Phys. Rev. A**77**, 062321 (2008).__Kwai-Kong Ng__and__Yung-Chung Chen__,*Supersolid phases in the bosonic extended Hubbard model*, Phys. Rev. B**77**, 052506 (2008).__Yu-Wen Lee__,*Quantum Phase Transitions and the Hidden Order in a Two-Chain Extended Boson Hubbard Model at Half-Odd-Integer Fillings*, Phys. Rev. B**77**, 064514 (2008).__Yu-Chin Tzeng__and__Min-Fong Yang__,*Scaling Properties of Fidelity in Spin-1 Anisotropic Model*, Phys. Rev. A**77**, 012311 (2008).__Chi-Tin Shih__, Stephan Roche, Rudolf A. Romer,*Point Mutations Effects on Charge Transport Properties of the Tumor-Suppressor Gene p53*, Phys. Rev. Lett.**100**, 018105 (2008).__Chi-Tin Shih__, Rudolf A. Romer, Stephan Roche,*Electric Transport Properties of the p53 Gene and the Effects of Point Mutations*, arXiv:0710.1676__Chi-Tin Shih__,*Sequence and Energy Dependence of Electric Transport Properties of DNA - A Tight-Binding Model Study*, Chinese Journal of Physics**45**, 703 (2007).__Min-Fong Yang__,*Ground-state fidelity in one-dimensional gapless models*, Phys. Rev. B**76**, 180403(R) (2007).__Yu-Wen Lee__, Yu-Li Lee,__Min-Fong Yang__,*Low-energy Effective Theory for One-dimensional Lattice Bosons near Integer Filling*, Phys. Rev. B**76**, 075117 (2007).- Yu-Li Lee and
__Yu-Wen Lee__,*Low-energy properties of the ferromagnetic metallic phase in manganites: Slave-fermion approach to the quantum double-exchange model*, Phys. Rev. B**75**, 064411 (2007). __Chi-Tin Shih__, Jian-Jheng Wu, C. P. Chou,__Yung-Chung Chen__and T. K. Lee,*Variational phase diagram of the electron-doped two-dimensional extended t-J model*, Chinese Journal of Physics**45**,207 (2007).__Kwai-Kong Ng__and T.K. Lee,*Field-induced supersolid phase in spin dimer XXZ systems*, JMMM,**310**, 1371 (2007).- Ya-Ru Wang, Zhi-Ming Bai, Ji-Qing Qiuz,
__Yung-Chung Chen__,*persistent current in two sub-rings coupled by one embedded quantum dot*,Int. J. Mod. Phys. B,**21**, 885 (2007). - Hsiang-Hsuan Hung, Chang-De Gong,
__Yung-Chung Chen__,__Min-Fong Yang__,*Search for quantum dimer phases and transitions in a frustrated spin ladder*, Phys. Rev. B**73**, 224433 (2006). - Yong-Jun Liu,
__Yung-Chung Chen__,__Min-Fong Yang__and Chang-De Gong,*Magnetic order of the two-dimensional antiferromagnetic 1/4-depleted square lattice*, Journal of Physics: Condensed matter**18**, 1805, (2006). __Min-Fong Yang__, Ming-Che Chang,*Streda-like formula in spin Hall effect*, Phys. Rev. B**73**, 073304 (2006).__Chi-Tin Shih__,*Electric transport and coding sequences of DNA molecules*, Physica Status Solidi (b)**243**, 378. (2006).- K. Y. Yang,
__C. T. Shih__, C. P. Chou, S. M. Huang, T. K. Lee, T. Xiang, and F. C. Zhang,*Low-energy physical properties of high-T-c superconducting Cu oxides: A comparison between the resonating valence bond and experiments*, Phys. Rev. B**73**, 224513 (2006). __Chi-Tin Shih__,*Characteristic length scale of electric transport properties of genomes*, Phys. Rev. E**74**, 010903(R) (2006).__Yu-Wen Lee__and Yu-Li Lee,*Quantum phases of a Feshbach-resonant atomic Bose gas in one dimension*, Phys. Rev. A**73**, 043606 (2006).__Kwai-Kong Ng__and T. K. Lee,*Supersolid Phase in Spin Dimer XXZ Systems under a Magnetic Field*, Phys. Rev. Lett.**97**, 127204 (2006).__Kwai-Kong Ng__and Ting-Kuo Lee,*Numerical study of magnetic field induced ordering in BaCuSi*, Phys. Rev. B_{2}O_{6}and related systems**73**, 014433 (2006).- T.K. Lee,
__Chi-Tin Shih__and Chang-Ming Ho,*Spectra of the high T*, Journal of Physics and Chemistry of Solids_{c}cuprates understood by the variational studies of the t-J-type models**67**,150-153 (2006). - Jing-Nuo Wu, Ming-Che Chang,
__Min-Fong Yang__,*Persistent spin current in mesoscopic ferrimagnetic spin ring*, Phys. Rev. B**72**, 172405 (2005). __Chi-Tin Shih__, Jian-Jheng Wu,__Yung-Chung Chen__, C-Y. Mou, C.-P. Chou, R.Eder, and T.K. Lee,*Antiferromagnetism and superconductivity of the two-dimensional extended t-J model*, Low Temperature Physics**31**, 757 (2005).__Chi-Tin Shih__,__Yung-Chung Chen__, T.K. Lee,*d-wave Pairing of the Two-Dimensional Extended t-J Model*, Chinese Journal of Physics**43**, 543 (2005).- Hong-Chi Chien,
__Yung-Chung Chen__,__Chi-Tin Shih__,*Pairing Correlation of the Two-dimensional Hubbard Model*, Chinese Journal of Physics**43**, 523 (2005). __Min-Fong Yang__,*Reexamination of entanglement and the quantum phase transition*, Phys. Rev. A**71**, 030302(R) (2005).