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We show in this paper that the technologically relevant field-like spin–orbit torque (SOT) shows resilience against the geometrical effect of electron backscattering. As a device grows smaller in size, the effect of geometry on physical properties like spin torque, and hence switching current could place a physical limit on the continued shrinkage of such a device — a necessary trend of all memory devices (MRAM). The geometrical effect of curves has been shown to impact quantum transport and topological transition of Dirac and topological systems. In our work, we have ruled out the potential threat of line curves degrading the effectiveness of SOT switching. In other words, SOT switching will be resilient against the influence of curves that line the circumferences of defects in the events of electron backscattering, which commonly happens in the channel of modern electronic devices. [ABSTRACT FROM AUTHOR]

Microcavity photon dynamics in curved space is an emerging interesting area at the crossing point of nanophotonics, chaotic science, and non-Euclidean geometry. We report the sharp difference between the regular and chaotic motions of cavity photons subjected to the varying space curvature. While the island modes of regular motion rise in the phase diagram in the curved space, the chaotic modes show special mechanisms to adapt to the space curvature, including the fast diffusion of ray dynamics, and the localization and hybridization of the Husimi wavepackets among different periodic orbits. These observations are unique effects enabled by the combination of the chaotic trajectory, the wave nature of light, and the non-Euclidean orbital motion, and therefore make the system a versatile optical simulator for chaotic science under quantum mechanics in curved space-time. [ABSTRACT FROM AUTHOR]

Self-assembly of nanoscale objects is of essential importance in materials science, condensed matter physics, and biophysics. Curvature modifies the principles and sequence of self-assembly in Euclidean space, resulting in unique and more complex structures. Understanding self-assembly behavior in curved space is not only instrumental for designing structural building blocks and assembly processes from a bottom-up perspective but is also critically important for delineating various biological systems. In this review, we summarize efforts made to unveil the physical nature of self-assembly in curved space through experiments and simulations. First, we outline the differences in the physical nature of self-assembly between curved space and Euclidean space by presenting relevant results of experiments and simulations. Second, we explore the principles of self-assembly in curved space at multiple scales and interactions, elucidating important factors that govern the self-assembly process from the perspectives of confinement and structural building blocks. Finally, we enumerate practical applications and control strategies for self-assembly in curved space and outline the challenges and prospects in this field. We hope that this review will encourage further efforts toward fundamental research and broaden the potential applications of designed assemblies in curved space. [ABSTRACT FROM AUTHOR]

Even in free space, which is commonly considered of as a flat space–time in most settings, the degree of polarization of a partially spatially coherent light beam changes as it travels. Similarly, the polarization degree would change when a partially spatially coherent light beam propagates in a curved space–time. The difference of the polarization degree between the curved space and flat space can reveal the essential structure of the curved space. In this work, we consider a simplest case of curved space known as Schwarzschild spacetime. We can simulate the Schwarzschild space–time as an optical material with an effective refractive index. The difference of the polarization degree of a light beam propagating in curved space and flat space can be achieved up to 5%, which is detectable in practical measurement. In addition, we have found that the partially spatially coherent light source is necessary for obtaining significant changes in polarization degree. Our results provide an alternative method to estimate the Schwarzschild radius of a massive object with the optical polarization degree measurement. • We consider the partially spatially coherent light in a three-dimensional curved space with the Schwarzschild space–time structure. • The polarization degree change is about 5 % away from the case of light propagation in a flat space, and this change is detectable in practical measurements. [ABSTRACT FROM AUTHOR]

We show how fabricated semiconductor heterostructures enable quantum particles to exhibit resilience to curved space, achieved through a suitable position-dependent mass distribution within the semiconductor. Following the proposed approach, we show that the first-order approximation of curved space requires a position-dependent mass distribution that is common for semiconductor heterostructures. For more complex structures of curved space, one has to consider a more exotic fabricated semiconductor. • Semiconductor heterostructure can resist space curvature for quantum particles. • Resisting curved space by heterostructures restores standard commutation relation. • Quantum potential quantifies heterostructure-curved space interplay. [ABSTRACT FROM AUTHOR]