English
Related papers

Related papers: A High-Performance Mid-infrared Optical Switch Ena…

200 papers

In this paper we report a detailed analysis of the temperature-dependent optical properties of epitaxially grown cadmium arsenide (Cd$_3$As$_2$), a newly discovered three-dimensional Dirac semimetal. Dynamic Fermi level tuning -- instigated…

Tunable mid-infrared lasers are essential for optical sensing and imaging. Existing technologies, however, face challenges in simultaneously achieving broadband spectral tunability and ultra-rapid scan rates, limiting their utility in…

Optics · Physics 2025-01-20 Xiaoshuai Ma , Tianjian Lv , Xudong Zhu , Ming Yan , Heping Zeng

A well known semiconductor Cd3As2 has reentered the spotlight due to its unique electronic structure and quantum transport phenomena as a topological Dirac semimetal. For elucidating and controlling its topological quantum state,…

Optical measurements and band structure calculations are reported on 3D Dirac materials. The electronic properties associated with the Dirac cone are identified in the reflectivity spectra of Cd$_3$As$_2$ and Na$_3$Bi single crystals. In…

Three dimensional (3D) Dirac semimetals are 3D analogue of graphene, which display Dirac points with linear dispersion in k-space, stabilized by crystal symmetry. Cd3As2 and Na3Bi were predicted to be 3D Dirac semimetals and were…

Materials Science · Physics 2015-08-28 Zhi-Gang Chen , Cheng Zhang , Yichao Zou , Enze Zhang , Lei Yang , Faxian Xiu , Jin Zou

Revealing the ultrafast dynamics of three-dimensional (3D) Dirac fermions upon photoexcitation is critical for both fundamental science and device applications. So far, how the cooling of 3D Dirac fermions differs from that of…

Mesoscale and Nanoscale Physics · Physics 2022-02-16 Changhua Bao , Qian Li , Sheng Xu , Shaohua Zhou , Xiang-Yu Zeng , Haoyuan Zhong , Qixuan Gao , Laipeng Luo , Dong Sun , Tian-Long Xia , Shuyun Zhou

Frequency multiplication of terahertz signals on a solid state platform is highly sought-after for the next generation of high-speed electronics and the creation of frequency combs. Solutions to efficiently generate extreme harmonics (up to…

Optics · Physics 2021-02-25 J. Lim , Y. S. Ang , F. J. G. de Abajó , I. Kaminer , L. K. Ang , L. J. Wong

We present analytic expressions for the electronic contributions to the linear conductivity $\sigma^{(1)}_{3d}(\omega)$ and the third order optical conductivity $\sigma^{(3)}_{3d}(\omega_1,\omega_2,\omega_3)$ of three dimensional massless…

Materials Science · Physics 2020-10-15 J. L. Cheng , J. E. Sipe , S. W. Wu

The three dimensional (3D) Dirac semimetal, which has been predicted theoretically, is a new electronic state of matter. It can be viewed as 3D generalization of graphene, with a unique electronic structure in which conduction and valence…

Mesoscale and Nanoscale Physics · Physics 2014-07-10 Sergey Borisenko , Quinn Gibson , Danil Evtushinsky , Volodymyr Zabolotnyy , Bernd Buechner , Robert J. Cava

The newly-emergent two-dimensional topological insulators (TIs) have shown their unique electronic and optical properties, such as good thermal management, high nonlinear refraction index and ultrafast relaxation time. Their narrow energy…

Optics · Physics 2015-05-26 Ke Yin , Tian Jiang , Xin Zheng , Hao Yu , Xiangai Cheng , Jing Hou

Tuning and stabilising topological states, such as Weyl semimetals, Dirac semimetals, or topological insulators, is emerging as one of the major topics in materials science. Periodic driving of many-body systems offers a platform to design…

Three-dimensional (3D) topological Dirac semimetal is a new kind of material that has a linear energy dispersion in 3D momentum space and can be viewed as an analog of graphene. Extensive efforts have been devoted to the understanding of…

Materials Science · Physics 2015-03-03 Enze Zhang , Yanwen Liu , Weiyi Wang , Cheng Zhang , Peng Zhou , Zhi-Gang Chen , Jin Zou , Faxian Xiu

The close approach of the Fermi energy EF of a Dirac semimetal to the Dirac point ED uncovers new physics such as velocity renormalization,1,2,3 and the Dirac plasma 4,5 at |EF -ED| < kBT, where kBT is the thermal energy. In graphene,…

Topological Dirac nodal-line semimetals host topologically nontrivial electronic structure with nodal-line crossings around the Fermi level, which could affect the photocarrier dynamics and lead to novel relaxation mechanisms. Herein, by…

Mesoscale and Nanoscale Physics · Physics 2024-05-21 Tianyun Lin , Yongkang Ju , Haoyuan Zhong , Xiangyu Zeng , Xue Dong , Changhua Bao , Hongyun Zhang , Tian-Long Xia , Peizhe Tang , Shuyun Zhou

Topological phases arise from the elegant mathematical structures imposed by the interplay between symmetry and topology1-5. From gapped topological insulators to gapless semimetals, topological materials in both quantum and classical…

Herein, $\mathrm{MoS_{2}}$ quantum dot (QDs) with controlled optical, structural, and electronic properties are synthesized using the femtosecond pulsed laser ablation in liquid (fs-PLAL) technique by varying pulse-width, ablation power,…

Raman scattering in the three-dimensional Dirac semimetal Cd3As2 shows an intricate interplay of electronic and phonon degrees of freedom. We observe resonant phonon scattering due to interband transitions, an anomalous anharmonicity of…

Materials Science · Physics 2017-07-05 A. Sharafeev , V. Gnezdilov , R. Sankar , F. C. Chou , P. Lemmens

There is still no general consensus on how one can describe the out-of-equilibrium phenomena in matter induced by an ultrashort light pulse. We investigate the pulse-induced dynamics in a layered Dirac semimetal SrMnBi2 by pump-and-probe…

Materials Science · Physics 2016-04-26 Y. Ishida , H. Masuda , H. Sakai , S. Ishiwata , S. Shin

Topological semimetals (TSMs) in which conduction and valence bands cross at zero-dimensional (0D) Dirac nodal points (DNPs) or 1D Dirac nodal lines (DNLs), in 3D momentum space, have recently drawn much attention due to their exotic…

Mesoscale and Nanoscale Physics · Physics 2018-12-05 Jianfeng Wang , Yizhou Liu , Kyung-Hwan Jin , Xuelei Sui , Wenhui Duan , Feng Liu , Bing Huang

Two-dimensional Dirac materials with a flat band have been demonstrated to possess a plethora of unusual electronic properties, but the optical properties of these materials are less studied. Utilizing $\alpha$-$\mathcal{T}_3$ lattice as a…

Mesoscale and Nanoscale Physics · Physics 2022-04-20 Chen-Di Han , Ying-Cheng Lai