Article
Nanoscience & Nanotechnology
Gaeun Choi, Jeongchun Ryu, Ryan Thompson, Jong-Guk Choi, Jimin Jeong, Sungjun Lee, Min-Gu Kang, Makoto Kohda, Junsaku Nitta, Byong-Guk Park
Summary: In this study, we investigate the Pt thickness dependence of spin-orbit torques (SOTs) in Co/Pt layers grown on different substrates. We find that the Co/Pt layers grown on single crystalline substrates show weaker thickness dependence of the SOT compared to those on SiO2 substrate, indicating the presence of a significant interfacial SOT effect at the Pt/substrate interface, particularly for thinner Pt.
Article
Multidisciplinary Sciences
Min-Gu Kang, Jong-Guk Choi, Jimin Jeong, Jae Yeol Park, Hyeon-Jong Park, Taehwan Kim, Taekhyeon Lee, Kab-Jin Kim, Kyoung-Whan Kim, Jung Hyun Oh, Duc Duong Viet, Jong-Ryul Jeong, Jong Min Yuk, Jongsun Park, Kyung-Jin Lee, Byong-Guk Park
Summary: The study demonstrates that electric field control of the Rashba effect in Pt/Co/AlOx structures can enable control of the spin-orbit torque and field-free switching of magnetization, providing a new method for electric field modulation of magnetism.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Simeng Xiang, Yanting Wu, Feng Wang, Zekun Lin, Zuofei Hong, Shaolin Ke
Summary: Theoretical investigation of time-domain dynamics in a non-Hermitian electric circuit network with anti-PT symmetry shows the ability to flexibly tune effective coupling strengths and on-site potentials. The system exhibits discrete diffraction, with constant intensity diffraction at the boundary between intermediate and broken phases. These results enrich the study of discrete diffraction and contribute to further exploration of topological phenomena.
RESULTS IN PHYSICS
(2021)
Article
Optics
Sebastian Schiffer, Xia-Ji Liu, Hui Hu, Jia Wang
Summary: We studied a generalized Aubry-Andre model that follows PT symmetry, and found a robust PT-symmetric phase that can support an Anderson localization transition. The model provides a perfect platform for studying disorder-driven localization phenomena in a PT-symmetric system.
Article
Chemistry, Inorganic & Nuclear
Meng-Meng Su, Jun Ni, Zhong-Cui Guo, Shu-Qin Liu, Jian-Jun Zhang, Chang-Gong Meng
Summary: This work synthesized six Pt(ii) complexes based on 4,4'-bis(triethylsilylethynyl)-2,2'-bipyridine ligand, showing long-wavelength NIR luminescence and reversible mechanoluminescence property. The enhanced MMLCT transitions are responsible for the long-wavelength NIR luminescence of the dimers, while reversible changes in intermolecular Pt⋯Pt distances drive the reversible mechanoluminescence property.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Nanoscience & Nanotechnology
Zhicheng Xiao, Andrea Alu
Summary: The study explores a hybrid parity-time and anti-parity-time symmetric system that supports highly tunable Fano resonances. This system can be implemented in nanophotonic and microwave circuits for real-time control of scattering line shapes, demonstrating the opportunities enabled by non-Hermitian platforms in controlling scattering line shapes for various photonic, electronic, and quantum systems. The potential applications include high-resolution imaging, switching, sensing, and multiplexing.
Article
Multidisciplinary Sciences
Javed Akram, Chao Zheng
Summary: In this study, we investigate the dynamics of entanglement in a PT-APT symmetric system for the first time. We also compare the entanglement dynamics in PT-PT symmetric systems, APT-APT symmetric systems, and PT-APT symmetric systems to gain further insights into non-Hermitian quantum systems and their environments. Our findings show that in the unbroken regime of the PT-APT symmetric system, entanglement oscillates with two different frequencies and can be well preserved for a long time when the non-Hermitian parts of the qubits are far from the exceptional points.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Multidisciplinary
Yuanjiang Tang, Chao Liang, Xin Wen, Weipeng Li, An-Ning Xu, Yong-Chun Liu
Summary: We propose a PT-symmetric feedback method to narrow the linewidths of resonance systems, achieving remarkable linewidth narrowing and enhancement of measurement sensitivity. By transforming a dissipative resonance system into a PT-symmetric system, using a quadrature measurement-feedback loop, the method only requires a single resonance mode, greatly extending its scope of applications. In a thermal ensemble of atoms, we demonstrate a 48-fold narrowing of the magnetic resonance linewidth and a 22-times improvement in measurement sensitivity in magnetometry, opening new avenues for studying nonHermitian physics and high-precision measurements in resonance systems with feedback.
PHYSICAL REVIEW LETTERS
(2023)
Review
Physics, Applied
Lijun Zhu, Daniel C. Ralph, Robert A. Buhrman
Summary: Platinum, with its giant spin Hall conductivity and compatibility with CMOS circuits, has the potential to be an outstanding provider of spin-orbit torques; however, pure clean-limit Pt with low resistivity still provides a low damping-like spin-orbit torque efficiency, limiting its practical applications; the efficiency of spin-orbit torque in Pt-based magnetic heterostructures can be significantly improved by increasing the spin Hall ratio of Pt and the spin transmissivity of the interfaces.
APPLIED PHYSICS REVIEWS
(2021)
Article
Mathematics
Alexei G. G. Kushner
Summary: The article presents a method for constructing exact and approximate solutions of evolutionary partial differential equations with several spatial variables, based on the theory of completely integrable distributions. Examples are provided to demonstrate the application of this method to calculate exact solutions of the generalized Kolmogorov-Petrovskii-Piskunov-Fishev equations with two space variables.
Article
Physics, Multidisciplinary
Sebae Park, Dongjin Lee, Kyungdeuk Park, Heedeuk Shin, Youngsun Choi, Jae Woong Yoon
Summary: In this study, an optical anti-parity-time (APT) symmetric system was created using a conventional fiber to demonstrate photonic APT-symmetric effects, such as energy-difference conservation and synchronized power oscillation. The results provide a theoretical and experimental framework linking non-Hermitian physics with technologically important nonlinear fiberoptic interactions.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Mathematical
Tommy Ohlsson, Shun Zhou
Summary: The study focuses on the transition probabilities of flavor eigenstates in a two-level quantum system described by a non-Hermitian Hamiltonian with PT symmetry, particularly looking at the PT-broken phase and exceptional points. The investigation reveals attributes of unbounded transition probabilities and global decay effects in the system.
JOURNAL OF MATHEMATICAL PHYSICS
(2021)
Article
Physics, Multidisciplinary
Yu-Liang Fang, Jun-Long Zhao, Yu Zhang, Dong-Xu Chen, Qi-Cheng Wu, Yan-Hui Zhou, Chui-Ping Yang, Franco Nori
Summary: This study experimentally demonstrates single-qubit coherence flow in PT- and APT-symmetric systems using an optical setup. Different periodic oscillations of coherence are observed in the symmetry unbroken regime, with two complete coherence backflows in one period in the PT-symmetric system and one backflow in the APT-symmetric system. The phenomenon of stable value of coherence flow is observed in the symmetry broken regime, and most experimental data agree with theoretical results within one standard deviation, suggesting potential avenues for future research in the dynamics of coherence in PT- and APT-symmetric systems.
COMMUNICATIONS PHYSICS
(2021)
Article
Optics
Tiecheng Wang
Summary: We have introduced generalized temporal coupled-mode theory for PT-symmetric optical resonator, and used it to explain the Fano resonance in PT-symmetric photonic heterostructures. Our theory's predictions match well with the simulated results from the transfer matrix method, confirming its accuracy. In contrast to conventional Fano resonance in optical resonators with time-reversal symmetry, this Fano resonance allows for a much larger range of tunable scattering coefficient amplitudes, which can exceed one and approach infinity at a singular scattering point.
Article
Optics
Enes Seker, Babak Olyaeefar, Khalil Dadashi, Serdar Sengul, Mohammad Hosain Teimourpour, Ramy El-Ganainy, Abdullah Demir
Summary: We experimentally demonstrate a new type of electrically pumped, large-area edge-emitting lasers that exhibit high power emission and high-quality beam. By establishing quasi PT-symmetry between two coupled cavities, the effective volume of higher-order modes is enlarged, allowing for selective pumping and filtering out higher-order modes. This work provides clear evidence of the utility of PT-symmetry in building lasers with enhanced performance and useful output power levels.
LIGHT-SCIENCE & APPLICATIONS
(2023)