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<jats:p>We report the structure and physical properties of two newly discovered compounds AV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub> and AV<jats:sub>6</jats:sub>Sb<jats:sub>6</jats:sub> (A = Cs, Rb), which have <jats:italic>C</jats:italic> <jats:sub>2</jats:sub> (space group: <jats:italic>Cmmm</jats:italic>) and <jats:italic>C</jats:italic> <jats:sub>3</jats:sub> (space group: <jats:inline-formula> <jats:tex-math> <?CDATA $R\bar{3}m$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>R</mml:mi> <mml:mover accent="true"> <mml:mrow> <mml:mn>3</mml:mn> </mml:mrow> <mml:mrow> <mml:mo stretchy="false">¯</mml:mo> </mml:mrow> </mml:mover> <mml:mi>m</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpl_38_12_127102ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>) symmetry, respectively. The basic V-kagome unit appears in both compounds, but stacking differently. A V<jats:sub>2</jats:sub>Sb<jats:sub>2</jats:sub> layer is sandwiched between two V<jats:sub>3</jats:sub>Sb<jats:sub>5</jats:sub> layers in AV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub>, altering the V-kagome lattice and lowering the symmetry of kagome layer from hexagonal to orthorhombic. In AV<jats:sub>6</jats:sub>Sb<jats:sub>6</jats:sub>, the building block is a more complex slab made up of two half-V<jats:sub>3</jats:sub>Sb<jats:sub>5</jats:sub> layers that are intercalated by Cs cations along the <jats:italic>c</jats:italic>-axis. Transport property measurements demonstrate that both compounds are nonmagnetic metals, with carrier concentrations at around 10<jats:sup>21</jats:sup> cm<jats:sup>−3</jats:sup>. No superconductivity has been observed in CsV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub> above 0.3 K under <jats:italic>in situ</jats:italic> pressure up to 46 GPa. Compared to CsV<jats:sub>3</jats:sub>Sb<jats:sub>5</jats:sub>, theoretical calculations and angle-resolved photoemission spectroscopy reveal a quasi-two-dimensional electronic structure in CsV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub> with <jats:italic>C</jats:italic> <jats:sub>2</jats:sub> symmetry and no van Hove singularities near the Fermi level. Our findings will stimulate more research into V-based kagome quantum materials.</jats:p>

<jats:p>It is known that p-type GeTe-based materials show excellent thermoelectric performance due to the favorable electronic band structure. However, n-type doping in GeTe is of challenge owing to the native Ge vacancies and high hole concentration of about 10<jats:sup>21</jats:sup> cm<jats:sup>−3</jats:sup>. In the present work, the formation energy of cation vacancies of GeTe is increased through alloying PbSe, and further Bi-doping enables the change of carrier conduction from p-type to n-type. As a result, the n-type thermoelectric performance is obtained in GeTe-based materials. A peak <jats:italic>zT</jats:italic> of 0.34 at 525 K is obtained for (Ge<jats:sub>0.6</jats:sub>Pb<jats:sub>0.4</jats:sub>)<jats:sub>0.88</jats:sub>Bi<jats:sub>0.12</jats:sub>Te<jats:sub>0.6</jats:sub>Se<jats:sub>0.4</jats:sub>. These results highlight the realization of n-type doping in GeTe and pave the way for further optimization of the thermoelectric performance of n-type GeTe.</jats:p>

<jats:p>We study electrical modulation of transport properties of silicene nanoconstrictions with different geometrical structures. We investigate the effects of the position and width of the central scattering region on the conductance with increasing Fermi energy. It is found that the conductance significantly depends on the position and the width of the nanoconstriction. Interestingly, the symmetrical structure of the central constriction region can induce a resonance effect and significantly increase the systemʼs conductance. We also propose a novel two-channel structure with an excellent performance on the conductance compared to the one-channel structure with the same total width. Such geometrically-induced conductance modulation of silicene nanostructures can be achieved in practice via current nanofabrication technology.</jats:p>

<jats:p>We report two new members of V-based kagome metals CsV<jats:sub>6</jats:sub>Sb<jats:sub>6</jats:sub> and CsV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub>. The most striking structural feature of CsV<jats:sub>6</jats:sub>Sb<jats:sub>6</jats:sub> is the V kagome bilayers. For CsV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub>, there is an intergrowth of two-dimensional V kagome layers and one-dimensional V chains, and the latter ones lead to the orthorhombic symmetry of this material. Further measurements indicate that these two materials exhibit metallic and Pauli paramagnetic behaviors. More importantly, different from CsV<jats:sub>3</jats:sub>Sb<jats:sub>5</jats:sub>, the charge density wave state and superconductivity do not emerge in CsV<jats:sub>6</jats:sub>Sb<jats:sub>6</jats:sub> and CsV<jats:sub>8</jats:sub>Sb<jats:sub>12</jats:sub> when temperature is above 2 K. Small magnetoresistance with saturation behavior and linear field dependence of Hall resistivity at high field and low temperature suggest that the carriers in both materials should be uncompensated with much different concentrations. The discovery of these two new V-based kagome metals sheds light on the exploration of correlated topological materials based on kagome lattice.</jats:p>

<jats:p>We report the synthesis and superconducting properties of a layered cage compound Ba<jats:sub>3</jats:sub>Rh<jats:sub>4</jats:sub>Ge<jats:sub>16</jats:sub>. Similar to Ba<jats:sub>3</jats:sub>Ir<jats:sub>4</jats:sub>Ge<jats:sub>16</jats:sub>, the compound is composed of 2D networks of cage units, formed by noncubic Rh–Ge building blocks, in marked contrast to the reported rattling compounds. The electrical resistivity, magnetization, specific heat capacity, and <jats:italic>μ</jats:italic>SR measurements unveiled moderately coupled s-wave superconductivity with a critical temperature <jats:italic>T</jats:italic> <jats:sub>c</jats:sub> = 7.0 K, the upper critical field <jats:italic>μ</jats:italic> <jats:sub>0</jats:sub> <jats:italic>H</jats:italic> <jats:sub>c2</jats:sub>(0) ∼ 2.5 T, the electron-phonon coupling strength <jats:italic>λ</jats:italic> <jats:sub>e−ph</jats:sub> ∼ 0.80, and the Ginzburg–Landau parameter <jats:italic>κ</jats:italic> ∼ 7.89. The mass reduction with the substitution of Ir by Rh is believed to be responsible for the enhancement of <jats:italic>T</jats:italic> <jats:sub>c</jats:sub> and coupling between the cage and guest atoms. Our results highlight the importance of atomic weight of framework in cage compounds in controlling the <jats:italic>λ</jats:italic> <jats:sub>e−ph</jats:sub> strength and <jats:italic>T</jats:italic> <jats:sub>c</jats:sub>.</jats:p>

<jats:p>Fast <jats:italic>in situ</jats:italic> switching of magnetic vortex core in a ferromagnetic nanodisk assisted by a nanocavity, with diameter comparable to the dimension of a vortex core, is systematically investigated by changing the strength as well as the diameter of the effective circular region of the applied magnetic field. By applying a local magnetic field within a small area at the nanodisk center, fast switching time of about 35 ps is achieved with relatively low field strength (70 mT) which is beneficial for fast data reading and writing. The reason for this phenomenon is that the magnetic spins around the nanocavity is aligned along the cavity wall due to the shape anisotropy when the perpendicular field is applied, which deepens the dip around the vortex core, and thus facilitates the vortex core switching.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Detection of ultralow magnetic field requires magnetic sensors with high sensitivity and low noise level, especially for low operating frequency applications. We investigated the transport properties of tunnel magnetoresistance (TMR) sensors based on the double indirect exchange coupling effect. The TMR ratio of about 150% was obtained in the magnetic tunnel junctions and linear response to an in-plane magnetic field was successfully achieved. A high sensitivity of 1.85%/Oe was achieved due to a designed soft pinned sensing layer of CoFeB/NiFe/Ru/IrMn. Furthermore, the voltage output sensitivity and the noise level of 10.7 mV/V/Oe, 10 nT/Hz<jats:sup>1/2</jats:sup> at 1 Hz and 3.3 nT/Hz<jats:sup>1/2</jats:sup> at 10 Hz were achieved in Full Wheatstone Bridge configuration. This kind of magnetic sensors can be used in the field of smart grid for current detection and sensing.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Topological edge flow and dissipationless odd viscosity are two remarkable features of chiral active fluids composed of active spinners. These features can significantly influence the dynamics of suspended passive particles and the interactions between the particles. By computer simulations, we investigate the transport phenomenon of anisotropic passive objects and the self-assembly behavior of passive spherical particles in the active spinner fluid. It is found that in confined systems, nonspherical passive objects can stably cling to boundary walls and are unidirectionally and robustly transported by edge flow of spinners. Furthermore, in an unconfined system, passive spherical particles are able to form stable clusters that spontaneously and unidirectionally rotate as a whole. In these phenomena, strong particle-wall and interparticle effective attractions play a vital role, which originate from spinner-mediated depletion-like interactions and can be largely enhanced by odd viscosity of spinner fluids. Our results thus provide new insight into the robust transport of cargoes and the nonequilibrium self-assembly of passive intruders.</jats:p>

<jats:p>Non-Hermitian materials can exhibit not only exotic energy band structures but also an anomalous velocity induced by non-Hermitian anomalous Berry connection as predicted by the semiclassical equations of motion for Bloch electrons. However, it is unclear how the modified semiclassical dynamics modifies transport phenomena. Here, we theoretically demonstrate the emergence of anomalous oscillations driven by either an external dc or ac electric field, which arise from non-Hermitian anomalous Berry connection. Moreover, it is a well-known fact that geometric structures of electric wave functions can only affect the Hall conductivity. However, we are surprised to find a non-Hermitian anomalous Berry connection induced anomalous linear longitudinal conductivity independent of the scattering time. We also show the emergence of a second-order nonlinear longitudinal conductivity induced by non-Hermitian anomalous Berry connection, violating a well-known fact of its absence in a Hermitian system with symmetric energy spectra. These anomalous phenomena are illustrated in a pseudo-Hermitian system with large non-Hermitian anomalous Berry connection. Finally, we propose a practical scheme to realize the anomalous oscillations in an optical system.</jats:p>

<jats:p>The interaction between optical solitons is of great significance for studying interaction between light and matter and development of all-optical devices, and is conducive to the design of integrated optical path. Optical soliton interactions for the nonlinear Schrödinger equation are investigated to improve the communication quality and system integration. Solutions of the equation are derived and used to analyze the interaction of two solitons. Some suggestions are put forward to weaken their interactions.</jats:p>