期刊：
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS,2019年256(11):1900185- ISSN：0370-1972
通讯作者：
Tang, Zhen-Kun;Chen, Mingyang
作者机构：
[Luo, Lin-Tao; Deng, Xiao-Hui; Zhang, Deng-Yu; Tang, Zhen-Kun] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;[Chen, Mingyang] Beijing Computat Sci Res Ctr, Beijing 100193, Peoples R China.
通讯机构：
[Tang, Zhen-Kun] H;[Chen, Mingyang] B;Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;Beijing Computat Sci Res Ctr, Beijing 100193, Peoples R China.
关键词：
density functional theory;semiconductor photocatalysts;two-dimensional heterostructures
摘要：
<jats:sec><jats:label /><jats:p>Semiconductor photocatalysts have received a lot of attention because of their wide range of applications in solving energy and environmental problems. In this work, the electronic structure and optical properties of two‐dimensional (2D) heterostructures of bismuth oxyhalides (BiOX, X = Cl, Br, I) and transition‐metal oxides (YO<jats:sub>3</jats:sub>, Y = Mo, W) are studied by density functional theory. The results reveal that the 2D BiOX–YO<jats:sub>3</jats:sub> heterostructures are semiconductors with band gaps of 0–1.41 eV. Electronic structure analyses indicate that the valence band maximum (VBM) and conduction band minimum (CBM) of BiOX–YO<jats:sub>3</jats:sub> are spatially separated and reside in the BiOX and YO<jats:sub>3</jats:sub> layers, respectively. The electron effective masses of BiOI–YO<jats:sub>3</jats:sub> (Y = Mo, W) heterostructures, especially BiOI–WO<jats:sub>3</jats:sub>, are significantly lower than those of BiOI and YO<jats:sub>3</jats:sub>. BiOI–YO<jats:sub>3</jats:sub> (Y = Mo, W) heterostructures exhibit a good absorption in the visible light region. The enhanced optoelectronic properties of BiOI–YO<jats:sub>3</jats:sub> are found to be related to the comparably large lattice mismatches between BiOI and YO<jats:sub>3</jats:sub>. The ultra‐low electron effective mass and good visible absorption of the BiOI–WO<jats:sub>3</jats:sub> heterostructure make it a promising candidate for the high‐efficient photocatalyts for water‐splitting.</jats:p></jats:sec>
作者机构：
[Yuan, Ji-Bing; Zhang, Deng-Yu; Tang, Shi-Qing] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.;[Yuan, Ji-Bing; Zhang, Deng-Yu; Tang, Shi-Qing] Hengyang Normal Univ, Hunan Prov Key Lab Intelligent Informat Proc & Ap, Hengyang 421008, Peoples R China.;[Peng, Zhao-Hui] Hunan Univ Sci & Technol, Inst Modern Phys, Xiangtan 411201, Peoples R China.;[Peng, Zhao-Hui] Hunan Univ Sci & Technol, Dept Phys, Xiangtan 411201, Peoples R China.;[Yuan, Ji-Bing; Tang, Shi-Qing] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct, Changsha 410081, Hunan, Peoples R China.
通讯机构：
[Tang, Shi-Qing] H;Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.;Hengyang Normal Univ, Hunan Prov Key Lab Intelligent Informat Proc & Ap, Hengyang 421008, Peoples R China.;Hunan Normal Univ, Key Lab Low Dimens Quantum Struct, Changsha 410081, Hunan, Peoples R China.;Hunan Normal Univ, Minist Educ, Dept Phys, Quantum Control, Changsha 410081, Hunan, Peoples R China.
关键词：
DIT;TRANSPARENCY;PHOTONIC;MOLECULE;EMITTER
摘要：
We theoretically investigate the transparency effect with a hybrid system composed of a photonic molecule and dipole emitter. It is shown that the transparency effect incorporates both the coupled resonator-induced transparency (CRIT) effect and the dipole-induced transparency (DIT) effect. It is found that the superposed transparency windows are consistently narrower than the CRIT and DIT transparency windows. Benefiting from the superposed transparency effect, the photonic Faraday rotation effect could be realized in the photonic molecule system, which is useful for entanglement generation and quantum information processing.
通讯机构：
[Wang, Xinwen] H;Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;Hengyang Normal Univ, Hunan Prov Key Lab Intelligent Informat Proc & Ap, Hengyang 421002, Peoples R China.;Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Minist Educ, Changsha 410081, Hunan, Peoples R China.
关键词：
One-step distillation;GHZ-type states;Local unitary equivalence;X states
摘要：
Entanglement distillation plays a very important role in quantum information science. Distillation of high-purity Greenberger–Horne–Zeilinger (GHZ) states has been widely studied. We here show that a pure GHZ-type entangled state or its local unitary (LU)-equivalent state could be extracted from two copies of a particular multipartite mixed state (e.g., an X state) in a single step. Such one-step distillation schemes for LU-equivalent states are expected to shed light on mixed-state manipulation and purification, as well as establish a link between entanglement classification and distillation.
作者机构：
[Zhang, Deng-Yu; Xu, Zhi-Feng; Tang, Zhen-Kun] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.;[Zhang, Deng-Yu; Xu, Zhi-Feng; Tang, Zhen-Kun] Hengyang Normal Univ, Coll Chem & Mat Sci, Hengyang 421008, Peoples R China.;[Hu, Shu-Xian; Lau, Woon-Ming; Tang, Zhen-Kun; Liu, Li-Min] Beijing Computat Sci Res Ctr, Beijing 100084, Peoples R China.;[Lau, Woon-Ming] Univ Sci & Technol Beijing, Sch Math & Phys, Ctr Green Innovat, Beijing 100083, Peoples R China.
通讯机构：
[Liu, Li-Min] B;Beijing Computat Sci Res Ctr, Beijing 100084, Peoples R China.
摘要：
<jats:title>Abstract</jats:title><jats:p>The suitable band structure is vital for perovskite solar cells, which greatly affect the high photoelectric conversion efficiency. Cation substitution is an effective approach to tune the electric structure, carrier concentration, and optical absorption of hybrid lead iodine perovskites. In this work, the electronic structures and optical properties of cation (Bi, Sn, and TI) doped tetragonal formamidinium lead iodine CH(NH<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub>PbI<jats:sub>3</jats:sub> (FAPbI<jats:sub>3</jats:sub>) are studied by first-principles calculations. For comparison, the cation-doped tetragonal methylammonium lead iodine CH<jats:sub>3</jats:sub>NH<jats:sub>3</jats:sub>PbI<jats:sub>3</jats:sub> (MAPbI<jats:sub>3</jats:sub>) are also considered. The calculated formation energies reveal that the Sn atom is easier to dope in the tetragonal MAPbI<jats:sub>3</jats:sub>/FAPbI<jats:sub>3</jats:sub> structure due to the small formation energy of about 0.3 eV. Besides, the band gap of Sn-doped MAPbI<jats:sub>3</jats:sub>/FAPbI<jats:sub>3</jats:sub> is 1.30/1.40 eV, which is considerably smaller than the un-doped tetragonal MAPbI<jats:sub>3</jats:sub>/FAPbI<jats:sub>3</jats:sub>. More importantly, compare with the un-doped tetragonal MAPbI<jats:sub>3</jats:sub>/FAPbI<jats:sub>3</jats:sub>, the Sn-doped MAPbI<jats:sub>3</jats:sub> and FAPbI<jats:sub>3</jats:sub> have the larger optical absorption coefficient and theoretical maximum efficiency, especially for Sn-doped FAPbI<jats:sub>3</jats:sub>. The lower formation energy, suitable band gap and outstanding optical absorption of the Sn-doped FAPbI<jats:sub>3</jats:sub> make it promising candidates for high-efficient perovskite cells.</jats:p>
作者机构：
[Yuan, Ji-Bing; Wang, Xin-Wen; Tang, Shi-Qing; Zhang, Deng -Yu] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;[Wang, Xin-Wen] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct, Changsha 410081, Peoples R China.;[Wang, Xin-Wen] Hunan Normal Univ, Quantum Control Minist Educ, Changsha 410081, Peoples R China.;[Wang, Xin-Wen] Hunan Normal Univ, Synerget Innovat Ctr Quantum Effects & Applicat, Changsha 410081, Peoples R China.;[Yuan, Ji-Bing] Inst Theoret Phys, CAB Key Lab Theoret Phys, Beijing 100190, Peoples R China.
通讯机构：
[Wang, Xin-Wen] H;Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.
关键词：
Entanglement purification;Non-GHZ-diagonal states;Non-asymptotic way;Perfect output states
摘要：
It has been shown that a nearly pure Greenberger-Horne-Zeilinger (GHZ) state could be distilled from a large (even infinite) number of GHZ-diagonal states that can be obtained by depolarizing general multipartite mixed states (non-GHZ-diagonal states) through sequences of (probabilistic) local operations and classical communications. We here demonstrate that perfect GHZ states can be extracted, with certain probabilities, from two copies of non-GHZ-diagonal mixed states when some conditions are satisfied. This result implies that it is not necessary to depolarize these entangled mixed states to the GHZ-diagonal type, and that they are better than GHZ-diagonal states for distillation of pure GHZ states. We find a wide class of multipartite entangled mixed states that fulfill the requirements. Moreover, we display that the obtained result can be applied to practical noisy environments, e.g., amplitude-damping channels. Our findings provide an important complementarity to conventional GHZ-state distillation protocols (designed for GHZ-diagonal states) in theory, as well as having practical applications.
