Yang Shengyuan

Assistant Professor

Research Areas:
Material Science,Electronics Engineering,Quantum Physics, Optics, Photonics

Pillar / Cluster: Engineering Product Development

Biography

Shengyuan Yang was from the city of Nanjing in the east part of China. After one year’s study in the Electrical Engineering program of Tsinghua University, he was awarded the Hong Kong Jockey Club Scholarship and transferred to study Mathematics/Physics at The University of Hong Kong. He graduated with First Class Honours in 2005. Then he joined the condensed matter theory group at The University of Texas at Austin and obtained his Ph.D. in physics degree in 2011. Dr. Yang’s past research is on the physical properties of novel materials and their nanostructures. The topics that he has worked on include electromotive force induced by magnetic dynamics, theory of optical second harmonic generation, properties of 2D materials, topological materials, pumping effects and nanoscale magnetic devices, and transport theory in disordered systems. He worked as an imaging geophysicist in CGG (US) Services at Houston from 2011 to 2013. He joined SUTD in June 2013.

Education

  • Ph.D. in Physics, The University of Texas at Austin, USA, 2011
  • B. Sc. in Mathematics/Physics, The University of Hong Kong, Hong Kong, 2005

Research Laboratory for Quantum Materials

website of RLQM

Research Interests

Dr. Yang’s research interests are focused on the field of theoretical condensed matter physics, with particular emphasis on the topological aspects in condensed matter systems, magnetic and transport properties of nanostructures, and properties of 2D novel materials. The aim is not only to deepen our understanding of the fundamental physics, but also to enable the application of such understanding for the technological development.

Dr. Yang’s current research interests include:

  1. Topological materials such as topological insulators, topological superconductors, topological semimetals etc. Topological materials have revolutionized our understanding of the fundamentals of solids. They are characterized by a special topological ordering and on their surfaces there are topological boundary states which can carry currents with low dissipation. These materials have promising applications in quantum electronics.
  2. Physical properties of novel 2D materials like graphene, silicene, transition metal dichalcogenides, 2D electrides etc. The 2D nature makes these materials behave quite differently from usual 3D materials. They hold great potential for constructing novel electronic devices.
  3. Spin pumping and spin transfer torque. The interplay between magnetic ordering and carrier transport is an intriguing research topic. Important effects like the GMR have enabled a tremendous increase of the information storage density. The objective here is to understand the fundamental physics and to design nano magnetic devices with new functions and better performance.

Various theoretical methods were used in research such as first-principles DFT calculations, semi-classical approach, tight-binding modeling, Green’s function method, non-equilibrium Schwinger-Keldysh technique, scattering approach, and various kinds of numerical techniques.

Students with a solid physics background who would like to pursue a PhD degree at SUTD or wish to have a short term exchange to SUTD are welcome to contact Dr. Yang directly.

Recent Research Highlights

  • Blue Phosphorene Oxide. As a variant of black phosphorene, blue phosphorene is a new 2D material recently realized in experiment. We predict that even more interesting physics appears when blue phosphorene is oxidated. The obtained blue phosphorene oxide (BPO) can host new topological phases with emergent topological fermions such as 2D pseudospin-1 fermions and double-Weyl fermions. The topological phases can be controlled by strain, and we predict a universal optical absorbance in its semimetal phase. [Nano Lett. 16, 6548 (2016)]
  • Exotic magnetoresponse in type-II Weyl semimetals. We show several distinct signatures in the magnetoresponse of type-II Weyl semimetals. The energy tilt tends to squeeze the Landau levels (LLs), and, for a type-II Weyl node, there always exists a critical angle between theBfield and the tilt, at which the LL spectrum collapses, regardless of the field strength. Before the collapse, signatures also appear in the magneto-optical spectrum, including the invariable presence of intraband peaks, the absence of absorption tails, and the special anisotropic field dependence. [Phys. Rev. Lett. 117, 077202 (2016)]
  • First 2D material exhibiting reversible bonding-nonbonding isostructrual and magnetic phase transitions. The change of bonding status, typically occurring only in chemical processes, could dramatically alter the material properties. We predict that a tunable breaking and forming of a diatomic bond can be achieved through physical means, i.e., by a moderate biaxial strain, in the newly discovered MoN2 two-dimensional (2D) material. Remarkably, the bonding change also induces a magnetic phase transition, during which the magnetic moments transfer from the N(2p) sublattice to the Mo(4d) sublattice; meanwhile, the type of magnetic coupling is changed from ferromagnetic to antiferromagnetic. This is the first time that such kind of phase transition is discovered in 2D materials. [Nano Lett. 16, 4576 (2016)]
  • Chirality Hall effect in Weyl semimetals. We generalize a semiclassical theory for lightly doped Weyl semimetals, taking into account various phase-space Berry curvatures. We predict universal transverse shifts of the wave-packet center in transmission and reflection, perpendicular to the direction in which the Fermi energy or velocities change adiabatically. The anomalous shifts are opposite for electrons with different chirality, and they can be made imbalanced by breaking inversion symmetry. We discuss how to utilize local gates, strain effects, and circularly polarized lights to generate and probe such a chirality-dependent Hall effect. [Phys. Rev. Lett. 115, 156603 (2015)]
  • Perfect topological valley filter. Like transistor for electronics, valley filter is the fundamental device for valleytronics. We propose the concept of topological valley filter, which is based on the topological 1D channels that are both valley-filtered and and propagating unidirectionally. As a result, such filters can in-principle achieve perfect performance with 100% valley filtering against possible scattering. Physically, it may be realized in valley-polarized QAH phase, or in domain walls between QAH and QVH phases. [Phys. Rev. B 91, 045404 (2015); Phys. Rev. B 92, 041404(R) (2015)]
  • Weyl-loop, Weyl-point, and Weyl-surface semimetals. We show that conjugated p-orbital interactions, common to most carbon allotropes, can produce novel topological spin-orbit-free Weyl semimetals. We predict a family of carbon allotrope materials which possess Weyl loops, Weyl points, or even Weyl surfaces, with different kinds of symmetry/topology protection. At a surface terminated by vacuum there emerges flat surface bands. [Nano Lett. 15, 6974 (2015); Nanoscale 8, 7232 (2016)]
  • Dirac semimetal thin films. Topological Dirac semimetals have been demonstrated in materials Na3Bi and Cd3As2 in 2014. We find interesting quantum confinement effects in their nanostructures. A gate electric field can be used to control the topological phase transition between a trivial insulator and a quantum spin Hall insulator. This offers a simple design of a topological field effect transistor in which the current is conducted in the topological edge channels with ultralow energy dissipation. [Scientific Reports 5, 7898 (2015); Scientific Reports 5, 14639 (2015)]
  • Scaling relation for anomalous Hall effect. With a history of more than 100 years, the anomalous Hall effect has been widely used as a standard tool for characterizing ferromagnets. However, a consistent microscopic theory for it only emerges in recent years. Particularly, complication arises due to multiple scattering sources, and there remains a basic conflict between theories and experiments on the scaling behavior of the anomalous Hall resistivity. We derive a general scaling relation involving multiple competing scattering mechanisms, described by a quadratic hypersurface in the space spanned by the partial resistivities. Our theory is confirmed by experiments on Fe films. [Phys. Rev. B 83, 125122 (2011); Phys. Rev. Lett. 114, 217203 (2015)]
  • Dirac and Weyl superconductors. We propose a new topological phase of matter: the Dirac superconductor, which has protected bulk 4-fold nodal points and surface Andreev arcs at zero energy. We provide a sufficient criterion for realizing them in centrosymmetric superconudctors with odd-parity pairing and mirror symmetry. The Dirac node could be gapped, evolve into a nodal ring, or split into a pair of Weyl nodes depending on the symmetry breaking of the system. We discuss the possible realization of such phases in Cu-doped Bi2Se3. [Phys. Rev. Lett. 113, 046401 (2014)]
  • Second order semiclassical theory. Semiclassical theory is a well-established formalism, presented in almost all solid state physics textbooks. The existing semiclassical theory is only accurate to the first order in external fields. We formulate a second order semiclassical theory. Remarkably, the equations of motion still maintain the same simple structure as in the first order theory, provided that the band energy and the Berry curvature are corrected to one higher order. This offers a powerful framework for studying various susceptibilities and nonlinear response coefficients. [Phys. Rev. Lett. 112, 166601 (2014); Phys. Rev. B 91, 214405 (2015)]
  • 2D electride materials. Electrides are a special kind of ionic solids with cavity-trapped electrons serving as the anions. Since their first discovery in 1983, several electride materials have been identified or synthesized. In 2013, a new kind of 2D electrides was discovered in Ca2N. Based on DFT calculations, we identified Ca2N and Sr2N as promising optical indefinite materials. Their few-layers are suitable plasmonic materials in the infrared range. We also predict that Ca2N monolayers have exceptional performance as anode materials for Na-ion batteries. [Scientific Reports 5, 12285 (2015); ACS Appl. Mater. Interfaces 7, 24016 (2015)]
  • Magnetic control for valleytronics. In 2D materials including (gapped) graphene, silicene, transition metal dichalcogenides, the low-energy states are massive Dirac fermions in multiple valleys. We find that these states have valley-contrasting orbital magnetic moment. Consequently, one can generate valley polarization by using external magnetic field. We further predict unusual physical effects including an anomalous contribution to the Hall current and novel magneto-transport properties in a pn junction. [Phys. Rev. B 88, 115140 (2013); RSC Advances 5, 83350 (2015)]

Key Publications

  • Yunwei Zhang, Weikang Wu, Yanchao Wang, S. A. Yang, and Yanming Ma, “Pressure-Stabilized Semiconducting Electrides in Alkaline-Earth Metal Subnitrides,” J. Am. Chem. Soc. DOI: 10.1021/jacs.7b07016.
  • Zhi-Ming Yu, Ying Liu, Yugui Yao, and S. A. Yang, “Unconventional pairing induced anomalous transverse shift in Andreev reflection,” arXiv:1708.06915.
  • Shan Guan, Ying Liu, Zhi-Ming Yu, Shan-Shan Wang, Yugui Yao, and S. A. Yang, “Novel Spin-Orbit Dirac Point in Monolayer HfGeTe,” arXiv:1706.08692.
  • Chengcheng Xiao, Fang Wang, S. A. Yang, and Yunhao Lu, “Ferroelectricity and Antiferroelectricity in Elemental Group-V Monolayer Materials,” arXiv:1706.05629.
  • Cong Chen, Shan-Shan Wang, Lei Liu, Zhi-Ming Yu, Xian-Lei Sheng, Ziyu Chen, and S. A. Yang, “Ternary wurtzite CaAgBi materials family: A playground for essential and accidental, type-I and type-II Dirac fermions,” Phys. Rev. Materials 1, 044201 (2017).
  • Ying Liu, Zhi-Ming Yu, and S. A. Yang, “Transverse Shift in Andreev Reflection,” Phys. Rev. B Rapid Comm. 96, 121101 (2017).
  • Ying Liu, S. A. Yang, and Fan Zhang, “Circular Dichroism and Radial Hall Effects in Topological Materials,” arXiv:1706.01020.
  • Pei Yang, Bo Tai, Weikang Wu, Jian-Min Zhang, Feng Wang, Shan Guan, Wei Guo, Yunhao Lu, and S. A. Yang, “Tailoring lanthanide doping in perovskite CaTiO3 for luminescence applications,” Phys. Chem. Chem. Phys. 19, 16189 (2017).
  • Chengyong Zhong, Yuanping Chen, Zhi-Ming Yu, Yuee Xie, Han Wang, S. A. Yang, and Shengbai Zhang, “Three-dimensional Pentagon Carbon with a genesis of emergent fermions,” Nat. Commun. 8, 15641 (2017).
  • Xiaoming Zhang, Zhi-Ming Yu, Xian-Lei Sheng, Hui Ying Yang, and S. A. Yang, “Coexistence of four-band nodal rings and triply-degenerate nodal points in centrosymmetric metal diborides,” Phys. Rev. B 95, 235116 (2017).
  • Shan Guan, Zhi-Ming Yu, Ying Liu, Gui-Bin Liu, Liang Dong, Yunhao Lu, Yugui Yao, and S. A. Yang, “Artificial gravity field, astrophysical analogues, and topological phase transitions in strained topological semimetals,” npj Quantum Materials 2, 23 (2017).
  • Si Li, Zhi-Ming Yu, Ying Liu, Shan Guan, Shan-Shan Wang, Xiaoming Zhang, Yugui Yao, and S. A. Yang, “Type-II nodal loops: Theory and material realization,” Phys. Rev. B Rapid Comm. 96, 081106 (2017).
  • Shan-Shan Wang, Ying Liu, Zhi-Ming Yu, Xian-Lei Sheng, and S. A. Yang, “Hourglass Dirac Chain Metal in Rhenium Dioxide,” arXiv:1705.01424.
  • Can Yesilyurt, Zhuo Bin Siu, Seng Ghee Tan, Gengchiau Liang, S. A. Yang, and Mansoor B. A. Jalil, “Anomalous tunneling characteristic of Weyl semimetals with tilted energy dispersion,” Appl. Phys. Lett. 111, 063101 (2017).
  • Tay-Rong Chang, Su-Yang Xu, Daniel S. Sanchez, Wei-Feng Tsai, Shin-Ming Huang, Guoqing Chang, Chuang-Han Hsu, Guang Bian, Ilya Belopolski, Zhi-Ming Yu, S. A. Yang, Titus Neupert, Horng-Tay Jeng, Hsin Lin, and M. Zahid Hasan, “Type-II Symmetry-Protected Topological Dirac Semimetals,” Phys. Rev. Lett. 119, 026404 (2017).
  • Yang Gao, S. A. Yang, and Qian Niu, “Intrinsic relative magnetoconductivity of nonmagnetic metals,” Phys. Rev. B 95, 165135 (2017).
  • Shengli Zhang, Wenhan Zhou, Yandong Ma, Jianping Ji, Bo Cai, S. A. Yang, Zhen Zhu, Zhongfang Chen, and Haibo Zeng, “Antimonene Oxides: Emerging Tunable Direct Bandgap Semiconductor and Novel Topological Insulator,” Nano Lett. 17, 3434 (2017).
  • Guoqing Chang, Su-Yang Xu, Shin-Ming Huang, Daniel S. Sanchez, Chuang-Han Hsu, Guang Bian, Zhi-Ming Yu, Ilya Belopolski, Nasser Alidoust, Hao Zheng, Tay-Rong Chang, Horng-Tay Jeng, S. A. Yang, Titus Neupert, Hsin Lin, and M. Zahid Hasan, “Nexus fermions in topological symmorphic crystalline metals,” Scientific Reports 7, 1688 (2017).
  • Shan Guan, Shao Ying Huang, Yugui Yao, and S. A. Yang, “Tunable hyperbolic dispersion and negative refraction in natural electride materials,” Phys. Rev. B 95, 165436 (2017).
  • Xian-Lei Sheng, Zhi-Ming Yu, Rui Yu, Hongming Weng, and S. A. Yang, “d-Orbital Topological Insulator and Semimetal in Antifluorite Cu2S Family: Contrasting Spin Helicities, Nodal Box, and Hybrid Surface States,” J. Phys. Chem. Lett. 8, 3506 (2017).
  • Chengcheng Xiao, Fang Wang, Yao Wang, S. A. Yang, Jianzhong Jiang, Ming Yang, Yunhao Lu, Shijie Wang, and Yuanping Feng, “Layer-dependent semiconductor-metal transition of SnO/Si(001) heterostructure and device application,” Scientific Reports 7, 2570 (2017).
  • Sai Gong, Wenhui Wan, Shan Guan, Bo Tai, Chang Liu, Botao Fu, S. A. Yang, Yugui Yao, “Tunable Half-metallic Magnetism in Atom-thin Holey Two-dimensional C2N Monolayer,” J. Mater. Chem. C 5, 8424 (2017).
  • Yafei Ren, Ke Wang, Xinzhou Deng, S. A. Yang, Jeil Jung, and Zhenhua Qiao, “Gate tunable current partition in graphene based topological zero lines,” Phys. Rev. B 95, 245420 (2017).
  • Fang Wang, Zhaohui Ren, He Tian, S. A. Yang, Yanwu Xie, Yunhao Lu, Jianzhong Jiang, Gaorong Han, and Kesong Yang, “Interfacial Multiferroics of TiO2/PbTiO3 Heterostructure Driven by Ferroelectric Polarization Discontinuity,” ACS Appl. Mater. Interfaces 9, 1899 (2017).
  • Liyan Zhu, Shan-Shan Wang, Shan Guan, Ying Liu, Tingting Zhang, Guibin Chen, and S. A. Yang, “Blue Phosphorene Oxide: Strain-tunable Quantum Phase Transitions and Novel 2D Emergent Fermions,” Nano Lett. 16, 6548 (2016).
  • Xiaoming Zhang, Zhi-Ming Yu, Shan-Shan Wang, Shan Guan, Hui Ying Yang, Yugui Yao, and S. A. Yang, “Theoretical prediction of MoN2 monolayer as a high capacity electrode material for metal ion batteries,” J. Mater. Chem. A 4, 15224 (2016).
  • S. A. Yang, “Dirac and Weyl Materials: Fundamental Aspects and Some Spintronics Applications,” SPIN 06, 1640003 (2016) (Invited Review); arXiv:1609.06482.
  • Fuming Chen, Lu Guo, Xiaoming Zhang, Zhi Yi Leong, S. A. Yang, and Hui Ying Yang, “Nitrogen-doped graphene oxide for effectively removing boron ions from seawater,” Nanoscale 9, 326 (2017).
  • Fangfang Tu, Junping Hu, Jian Xie, Gaoshao Cao, Shichao Zhang, S. A. Yang, Xinbing Zhao, and Hui Ying Yang, “Au-Decorated Cracked Carbon Tube Arrays as Binder-Free Catalytic Cathode Enabling Guided Li2O2 Inner Growth for High-Performance Li-O2 Batteries,” Adv. Funct. Mater. 26, 7725 (2016)
  • Xiaoming Zhang, Junping Hu, Yingchun Cheng, Hui Ying Yang, Yugui Yao, and S. A. Yang, “Borophene as an extremely high capacity electrode material for Li-ion and Na-ion batteries,” Nanoscale 8, 15340 (2016).
  • Zhi-Ming Yu, Yugui Yao, and S. A. Yang, “Predicted Unusual Magnetoresponse in Type-II Weyl Semimetals,” Phys. Rev. Lett. 117, 077202 (2016).
  • Zhenhua Qiao, Yulei Han, Lei Zhang, Ke Wang, Xinzhou Deng, Hua Jiang, S. A. Yang, Jian Wang, and Qian Niu, “Anderson Localization from Berry-Curvature Interchange in Quantum Anomalous Hall Systems,” Phys. Rev. Lett. 117, 056802 (2016).
  • Yao Wang, Shan-Shan Wang, Yunhao Lu, Jianzhong Jiang, and S. A. Yang, “Strain-Induced Isostructural and Magnetic Phase Transitions in Monolayer MoN2,” Nano Lett. 16, 4576 (2016).
  • Yunhao Lu, Di Zhou, Guoqing Chang, Shan Guan, Weiguang Chen, Yinzhu Jiang, Jianzhong Jiang, Xue-sen Wang, S. A. Yang, Yuan Ping Feng, and Yoshiyuki Kawazoe, and Hsin Lin, “Multiple Unpinned Dirac Fermion States in 2D Materials with Phosphorene Lattice Structure,” npj Computational Materials 2, 16011 (2016).
  • Junping Hu, Bo Xu, Chuying Ouyang, Ying Zhang, and S. A. Yang, “Investigations on Nb2C monolayer as promising anode material for Li or non-Li ion batteries from first-principles calculations,” RSC Advances 6, 27467 (2016).
  • Chengyong Zhong, Yuanping Chen, Yuee Xie, S. A. Yang, Marvin L. Cohen, and Shengbai Zhang, “Towards Three-Dimensional Weyl-Surface Semimetals in Graphene Networks,” Nanoscale 8, 7232 (2016).
  • Yunhao Lu, Di Zhou, Tao Wang, S. A. Yang, and Jianzhong Jiang, “Topological Properties of Atomic Lead Film with Honeycomb Structure,” Scientific Reports 6, 21723 (2016).
  • Qingyun Zhang, S. A. Yang, Wenbo Mi, Yingchun Cheng, and Udo Schwingenschlögl, “Large Spin-Valley Polarization in Monolayer MoTe2 on Top of EuO(111),” Advanced Materials 28, 959 (2016).
  • Xianbo Xiao, Ying Liu, Zhengfang Liu, Guoping Ai, S. A. Yang, and Guanghui Zhou, “All-electric spin modulator based on a two-dimensional topological insulator,” Appl. Phys. Lett. 108, 032403 (2016).
  • Shan Guan, Yingchun Cheng, Chang Liu, Junfeng Han, Yunhao Lu, S. A. Yang, and Yugui Yao, “Effects of strain on electronic and optic properties of holey two-dimensional C2N crystals,” Appl. Phys. Lett. 107, 231904 (2015).
  • Gang Liu, Shi-Bing Liu, Bo Xu, Chuying Ouyang, H. Y. Song, Shan Guan, and S. A. Yang, “Multiple Dirac Points and Hydrogenation-Induced Magnetism of Germanene Layer on Al (111) Surface,” J. Phys. Chem. Lett. 6, 4936 (2015).
  • Junping Hu, Bo Xu, S. A. Yang, Shan Guan, Chuying Ouyang, and Yugui Yao, “2D Electrides as Promising Anode Materials for Na-Ion Batteries from First-Principles Study,” ACS Appl. Mater. Interfaces 7, 24016 (2015).
  • Liyan Zhu, Tingting Zhang, Ziming Sun, Jianhua Li, Guibin Chen, and S. A. Yang, “Thermal conductivity of biaxial-strained MoS2: sensitive strain dependence and size dependent reduction rate,” Nanotechnology 26, 465707 (2015).
  • Yuanping Chen, Yuee Xie, S. A. Yang, Hui Pan, Fan Zhang, Marvin L. Cohen, and Shengbai Zhang, “Nanostructured Carbon Allotropes with Weyl-like Loops and Points,” Nano Lett. 15, 6974 (2015).
  • S. A. Yang, Hui Pan, and Fan Zhang, “Chirality-dependent Hall Effect in Weyl Semimetals,” Phys. Rev. Lett. 115, 156603 (2015).
  • Hui Pan, Meimei Wu, Ying Liu, and S. A. Yang, “Electric control of topological phase transitions in Dirac semimetal thin films,” Scientific Reports 5, 14639 (2015).
  • S. A. Yang, Hui Pan, and Fan Zhang, “Buckled honeycomb lattice and unconventional magnetic response,” RSC Advances 5, 83350 (2015).
  • Shan Guan, S. A. Yang, Liyan Zhu, Junping Hu, Yugui Yao, “Electronic, Dielectric, and Plasmonic Properties of Two-Dimensional Electride Materials X2N (X=Ca, Sr): A First-Principles Study,” Scientific Reports 5, 12285 (2015).
  • Hui Pan, Xin Li, Fan Zhang, and S. A. Yang, “Perfect valley filter in a topological domain wall,” Phys. Rev. B Rapid Comm. 92, 041404(R) (2015).
  • Dazhi Hou, Gang Su, Yuan Tian, Xiaofeng Jin, S. A. Yang, and Qian Niu, “Multivariable Scaling for the Anomalous Hall Effect,” Phys. Rev. Lett. 114, 217203 (2015).
  • Yang Gao, S. A. Yang, and Qian Niu, “Geometrical effects in orbital magnetic susceptibility,” Phys. Rev. B 91, 214405 (2015).
  • Xianbo Xiao, S. A. Yang, Zhengfang Liu, Huili Li, and Guanghui Zhou, “Anisotropic Quantum Confinement Effect and Electric Control of Surface States in Dirac Semimetal Nanostructures,” Scientific Reports 5, 7898 (2015).
  • Hui Pan, Xin Li, Hua Jiang, Yugui Yao, and S. A. Yang, “Valley-polarized quantum anomalous Hall phase and disorder-induced valley-filtered chiral edge channels,” Phys. Rev. B 91, 045404 (2015).
  • Hui Pan, Xin Li, Zhenhua Qiao, Cheng-Cheng Liu, Yugui Yao, and S. A. Yang, “Topological metallic phases in spin–orbit coupled bilayer systems,” New J. Phys. 16, 123015 (2014).
  • Junping Hu, Bo Xu, Chuying Ouyang, S. A. Yang, and Yugui Yao, “Investigations on V2C and V2CX2 (X=F, OH) Monolayer as a Promising Anode Material for Li Ion Batteries from First-Principles Calculations,” J. Phys. Chem. C 118(42), 24274 (2014).
  • Cheng-Cheng Liu, Shan Guan, Zhigang Song, S. A. Yang, Jinbo Yang, and Yugui Yao, “Low-energy effective Hamiltonian for giant-gap quantum spin Hall insulators in honeycomb X-hydride/halide (X=N–Bi) monolayers,” Phys. Rev. B 90, 085431 (2014).
  • S. A. Yang, Hui Pan, and Fan Zhang, “Dirac and Weyl Superconductors in Three Dimensions,” Phys. Rev. Lett. 113, 046401 (2014).
  • Yang Gao, S. A. Yang, and Qian Niu, “Field Induced Positional Shift of Bloch Electrons and Its Dynamical Implications,” Phys. Rev. Lett. 112, 166601 (2014).
  • Jin-Jian Zhou, Wanxiang Feng, Ying Zhang, S. A. Yang, and Yugui Yao, “Engineering Topological Surface States and Giant Rashba Spin Splitting in BiTeI/Bi2Te3 Heterostructures,” Scientific Reports 4, 3841 (2014).
  • Tianyi Cai, S. A. Yang, Xiao Li, Fan Zhang, Junren Shi, Wang Yao, and Qian Niu, “Magnetic control of the valley degree of freedom of massive Dirac fermions with application to transition metal dichalcogenides,” Phys. Rev. B 88, 115140 (2013).
  • Guobao Zhu, S. A. Yang, Cheng Fang, Wu Ming Liu, and Yugui Yao, “Theory of orbital magnetization in disordered systems,” Phys. Rev. B 86, 214415 (2012).
  • S. A. Yang, Zhenhua Qiao, Yugui Yao, Junren Shi, and Qian Niu, “Singular effects of spin-flip scattering on gapped Dirac fermions,” Europhys. Lett95, 67001 (2011).
  • S. A. Yang, Hui Pan, Yugui Yao, and Qian Niu, “Scattering universality classes of side jump in anomalous Hall effect,” Phys. Rev. B 83, 125122 (2011).
  • Zhenhua Qiao, S. A. Yang, Bin Wang, Yugui Yao, and Qian Niu, “Spin-polarized and valley-associated edge modes in graphene nanoribbons,” Phys. Rev. B 84, 035431 (2011).
  • S. A. Yang, Qian Niu, D. A. Pesin, and Allan H. MacDonald, “Theory of I-V characteristics of magnetic Josephson junctions,” Phys. Rev. B 82, 184402 (2010).
  • S. A. Yang, Geoffrey S. D. Beach, Carl Knutson, Di Xiao, Zhenyu Zhang, Maxim Tsoi, Qian Niu, Allan H. MacDonald, and James L. Erskine, “Topological electromotive force from domain-wall dynamics in a ferromagnet,” Phys. Rev. B 82, 054410 (2010).
  • Zhenhua Qiao, S. A. Yang, Wanxiang Feng, Wong-Kong Tse, Jun Ding, Yugui Yao, Jian Wang, and Qian Niu, “Quantum anomalous Hall effect in graphene from Rashba and exchange effects,” Phys. Rev. B Rapid Comm82, 161414(R) (2010).
  • S. A. Yang, Xiaoqin Li, A. D. Bristow, and J. E. Sipe, “Second harmonic generation from tetragonal centrosymmetric crystals,” Phys. Rev. B 80, 165306 (2009).
  • Wang Yao, S. A. Yang, and Qian Niu, “Edge States in Graphene: From Gapped Flat-Band to Gapless Chiral Modes,” Phys. Rev. Lett102, 096801 (2009).
  • S. A. Yang, Geoffrey S. D. Beach, Carl Knutson, Di Xiao, Qian Niu, Maxim Tsoi, and James L. Erskine, “Universal Electromotive Force Induced by Domain Wall Motion,” Phys. Rev. Lett102, 067201 (2009).

Conference Talks and Seminars

  • Seminar Talk, “Novel Optical Response in Topological Materials,” Nanjing Normal University, Jul. 17, 2017.
  • Seminar Talk, “On d-orbital Topological Material & First Elemental Ferroelectric Material,” Beijing Institute of Technology, Jul. 15, 2017.
  • Invited Speaker, “Dirac Superconductor & Topological Phase Transitions in Dirac semimetal,” The 7th ICQs Annual Workshop, Beijing, Jul. 13, 2017.
  • Invited Speaker, “Novel Types of Topological Semimetals and Topological Phase Transitions,” The 3rd Conference on Condensed Matter Physics, Shanghai, Jun. 25, 2017.
  • Seminar Talk, “Topological Carbon and Hourglass Dirac Chain Metal,” Nanjing University, Jun. 23, 2017.
  • Speaker, “Controlled Quantum Phase Transitions in Novel 2D Materials,” ICMAT 2017 Conference, Singapore, Jun. 21, 2017.
  • Seminar Talk, “Electride Materials for Plasmonic, Energy Storage, and Optical Applications,” National University of Singapore, Apr. 21, 2017.
  • Invited Speaker, “Novel Quantum Phase Transitions Generated by Strain,” The 10th International Conference on Computational Physics, Macao, Jan. 18, 2017.
  • Seminar Talk, “Novel Dirac/Weyl materials and magnetoresponse of type-II Weyl semimetals,” South University of Science and Technology of China, Aug. 9, 2016.
  • Speaker, “Topological Semimetals and Valley-Dependent Electronics,” ICPS 2016, Beijing, Aug. 4, 2016.
  • Speaker, “Reversible Bonding-Nonbonding Isostructural and Magnetic Phase Transitions in 2D Material,” The 2nd Conference on Condensed Matter Physics, Nanjing, Jul. 21, 2016.
  • Speaker, “Unusual Magneto-Response of Type-II Weyl Semimetals,” The 2nd Conference on Condensed Matter Physics, Nanjing, Jul. 20, 2016.
  • Invited Speaker, “Dirac and Weyl Materials: Fundamental Aspects and Some Applications,” 2016 International Workshop on Emerging Electronic Materials and Devices, Hefei, Jul. 10, 2016.
  • Speaker, “Topological Semimetals in Nanostructured Carbon Materials,” IUMRS-ICEM 2016, Singapore, Jul. 6, 2016.
  • Seminar Talk, “Valleytronics, Chiral Fermions, and Topological Materials,” Nanjing Normal University, May 23, 2016.
  • Seminar Talk, “Dirac Materials: Fundamentals and Some Potential Applications,” Zhejiang University, May 20, 2016.
  • Seminar Talk, “Topological Materials and Emergent Chiral Fermions,” Nanjing Tech University, May 19, 2016.
  • Poster Presentation, “Unusual Properties of 2D Electride Materials,” The Croucher Advanced Study Institute, The University of Hong Kong, May 5, 2016.
  • Invited Speaker, “Topological Semimetals and Chirality-Dependent Electron Dynamics,” Institute of Physics of Singapore 2016 Conference, SUTD, Mar. 7, 2016.
  • Invited Speaker, “Dirac Valleytronics and Topological Materials,” NTU/UniLu Joint Workshop on Topological Phases, Nanyang Technological University, Jan. 18, 2016.
  • Seminar Talk, “Topological Materials and Valleytronics,” South University of Science and Technology of China, Aug. 14, 2015.
  • Invited Speaker, “2D Electride Materials for Optical, Plasmonic, and Energy Storage Applications,” 1st Conference of Condensed Matter Physics, Beijing, Jul. 16, 2015.
  • Invited Speaker, “Electronic, Dielectric, and Plasmonic Properties of 2D Electride Materials: Ca2N and Sr2N,” ICMAT 2015 & IUMRS-ICA 2015, Singapore, Jul. 3, 2015.
  • Speaker, “Topological Properties of Two-dimensional Spin-orbit Coupled Materials,” ICMAT 2015 & IUMRS-ICA 2015, Singapore, Jul. 2, 2015.
  • Seminar Talk, “Some Geometrical and Topological Aspects in Valleytronics,” International Center for Quantum Materials, Peking University, May 21, 2015.
  • Seminar Talk, “Geometrical and Topological Valley Physics in Solid State Materials,” Nanjing University of Science and Technology, May 11, 2015.
  • Seminar Talk, “Geometrical and Topological Valley Physics in Solid State Materials,” Central South University, May 7, 2015.
  • Seminar Talk, “Geometrical and Topological Valley Physics in Solid State Materials,” Hunan Normal University, May 6, 2015.
  • Invited Speaker, “Geometrical and Topological Aspects in Valley Physics,” Institute of Physics of Singapore 2015 Conference, Nanyang Technological University, Mar. 3, 2015.
  • Invited Speaker, “Dirac and Weyl Superconductors in Three Dimensions,” The 9th International Conference on Computational Physics, National University of Singapore, Jan. 10, 2015.
  • Seminar Talk, “Novel Topological Phases in Condensed Matter,” NUS Surface Science Journal Club, Oct. 16, 2014.
  • Speaker, “Dirac and Weyl Superconductors in Three Dimensions,” 18th National Conference on Condensed Matter Theory and Statistical Physics, Chongqing University, Jul. 29, 2014.
  • Speaker, “Novel Topological Phases in 2D Buckled Honeycomb Lattices,” 18th National Conference on Condensed Matter Theory and Statistical Physics, Chongqing University, Jul. 29, 2014.
  • Seminar Talk, “Some Topological Effects in Condensed Matter Physics,” Xiangtan University, Jul. 23, 2014.
  • Invited Speaker, “Dirac and Weyl Superconductors in Three Dimensions,” 13th International Conference on Condensed Matter Theory and Computational Materials Science, Sichuan University, Jul. 15, 2014.
  • Poster Presentation, “Dirac and Weyl Superconductors in Three Dimensions,” OCPA8 Conference, Nanyang Technological University, Jun. 24, 2014.
  • Invited Speaker, “Dirac and Weyl Superconductors in Three Dimensions,” International Forum for Young Scholars, University of Electronic Science and Technology of China, Apr. 1, 2014.
  • Seminar Talk, “Topological Effects in Condensed Matter: a Few Topics,” South China Normal University, Mar. 11, 2014.
  • Seminar Talk, “Anomalous Hall Effect: the correct scaling formula,” Fudan University, Dec. 23, 2013.
  • Invited Speaker, “Magnetic Control of Valley Degree of Freedom,” The Hong Kong Forum of Physics: Novel Quantum Systems, The University of Hong Kong, Dec. 12, 2013.
  • Seminar Talk, “Some Research Topics in Condensed Matter Physics,” Beihang University, Oct. 10, 2013.
Research Interest

  • Condensed Matter Physics
  • Topology in Solid State Physics
  • Material Physics
  • Transport Modeling and Theory
  • Spintronics, Magnetic Devices
Group Openings

  • Currently recruiting PhD students of 2018 Intake. If interested, please email Dr. Yang for more information.
  • Postdoc Research Fellow position available.