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:
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(NH2) 2PbI3 (FAPbI(3)) are studied by first-principles calculations. For comparison, the cation-doped tetragonal methylammonium lead iodine CH3NH3PbI3 (MAPbI(3)) are also considered. The calculated formation energies reveal that the Sn atom is easier to dope in the tetragonal MAPbI(3)/FAPbI(3) structure due to the small formation energy of about 0.3 eV. Besides, the band gap of Sn-doped MAPbI(3)/FAPbI(3) is 1.30/1.40 eV, which is considerably smaller than the un-doped tetragonal MAPbI(3)/FAPbI(3). More importantly, compare with the un-doped tetragonal MAPbI(3)/FAPbI(3), the Sn-doped MAPbI(3) and FAPbI(3) have the larger optical absorption coefficient and theoretical maximum efficiency, especially for Sndoped FAPbI(3). The lower formation energy, suitable band gap and outstanding optical absorption of the Sn-doped FAPbI(3) make it promising candidates for high-efficient perovskite cells.
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.
摘要:
We study temperature effects on non-Markovian dynamics in a model of an atomic impurity qubit immersed in a quasi-two-dimensional dipolar Bose-Einstein condensate , which can be described as a pure dephasing spin-boson model. We use the measure proposed by Breuer et al. (Phys Rev Lett 103:210401, 2009) to characterize non-Markovianity of the quantum process and find for larger relative dipole-dipole interaction, properly low temperature can induce the non-Markovianity enhancement. We give an explanation of the non-Markovianity enhancement that raising temperature can increase the sharpness of the temperature-dependent environmental spectral density.
摘要:
An intermediate connector of Cs2CO3/Al/MoO3 used in tandem organic light-emitting diodes (OLEDs) was investigated in this work. Here, an ultrathin Cs2CO3/Al was used as an electron-injection layer (EIL) from MoO3 to the adjacent electron transporting layer (ETL). To verify the function of this intermediate connector, the device performances were evaluated through current density-voltage-luminance characteristics, current density-efficiency curves, and EL spectra. Additionally, the effect of photon energy on carriers behavior in the Cs2CO3/Al/MoO3 connector is also estimated. The electrical properties and EL spectra of tandem OLEDs show that the Cs2CO3/Al/MoO3 can function well for charge generation and transport, and the current density-voltage curves of Cs2CO3/Al/MoO3 based special multilayer device shows the photovoltaic effect as a photovoltaic cell.