The inverse design of metamaterials with desired properties represents a significant challenge in mechanical science. Despite the potential demonstrated by recent algorithm models, their adoption has been limited by constraints such as the geometric limitations of elementary building cells. The use of the kirigami principle, which offers large deformation and nonlinear stiffness, has been explored. However, existing kirigami geometries, which remain isotropic, may restrict the design space. Our objective is to leverage the capabilities of geometry in shape programming and transformation to provide a framework for inverse design. This framework utilizes a unified geometry in kirigami cutting that is easily parameterized to generate independent anisotropic deformation and bistability. By integrating machine learning with a genetic algorithm, we achieve an inverse design process. The resulting kirigami architectures can be preprogrammed into target shapes and transformed between multiple stable states. This work underscores the significance of cell geometry topology, offering a powerful tool for the inverse design of metamaterials with reconfigurable and tailored mechanical properties, applicable in various fields such as robotics, electronics, and beyond.

Pure dephasing and spontaneous emission are two nonunitary processes of atoms or spins interacting with fluctuating electromagnetic (EM) modes. The dissipative collective emission processes (e.g., superradiance) originate from interactions with EM modes in resonance with atoms and have received considerable attention. Meanwhile, the analogous nondissipative collective dephasing phenomena mediated by EM environments remain poorly understood. Here, we introduce the nano-EM superdephasing phenomenon arising in the photonic environments near materials. We show that collective dephasing in this nano-EM environment is enhanced by over 10 orders of magnitude compared to free space or cavities. This giant enhancement originates from long-range correlations in off-resonant, low-frequency evanescent EM fluctuations, which lead to collectively accelerated (super) or suppressed (sub) dephasing in many-body entangled states. We further unravel that nano-EM collective dephasing exhibits universal interaction ranges near materials with different anisotropies that can be reciprocal or nonreciprocal. This nano-EM interaction range, which is not present in free space and cavities, leads to unique scaling laws of superdephasing in Greenberger-Horne-Zeilinger states different from the conventional $N^2$ scaling of superradiance. Finally, we discuss how to experimentally isolate and control superdephasing to open interesting frontiers for scalable quantum systems.

Disorder effects in hybrid semiconductor-superconductor (SM-SC) nanowires, widely recognized as the main obstacle to realizing stable Majorana zero modes (MZMs) in these structures, have been systematically investigated theoretically in recent years. However, there are no corresponding detailed studies of disorder effects in planar Josephson junction (JJ) structures, which represent a promising alternative to the Majorana nanowire platform. In this paper, we perform a numerical analysis of the low-energy physics of JJ structures based on an effective microscopic model that includes two types of disorder, charge impurities inside the semiconductor and roughness on the surface of the superconducting film. We consider different parameter regimes, including low and high chemical potential values, weak and strong effective SM-SC coupling strengths, and weak and strong disorder strengths. The results are benchmarked using disordered hybrid nanowires realized in planar SM-SC structures similar to those involved in the fabrication of Josephson junctions and having similar model parameters and disorder strengths. We find that the topological superconducting phase hosted by a JJ structure is, generally, more robust against disorder than the topological superconductivity realized in a hybrid nanowire with similar parameters. On the other hand, we find that operating the JJ in a regime characterized by large values of chemical potential results in huge finite-size effects that can destroy the stability of MZMs.

In this study, we provide a full experimental characterization of the parametric longitudinal coupling between a complementary metal oxide semiconductor (CMOS) charge qubit and an off-chip rf resonator. Following Corrigan et al., Phys. Rev. Appl. 20, 064005 (2023), we activate parametric longitudinal coupling by driving the charge qubit at the resonator frequency. Managing the crosstalk between the drive applied to the qubit and the resonator allows for the systematic study of the dependence of the longitudinal and dispersive charge-photon couplings on the qubit-resonator detuning and the applied drive. Our experimental estimations of the charge-photon couplings are perfectly reproduced by theoretical simple formulas, without relying on any fitting parameter. We go further by showing a parametric displacement of the resonator’s steady state, conditional on the qubit state, and the insensitivity of the longitudinal coupling constant to the photon population of the resonator. Our results pave the way for the exploration of the photon-mediated longitudinal readout and coupling of multiple and distant spins, with long coherent times, in hybrid CMOS circuit quantum electrodynamics architectures.

Quantum-mechanics-based transport calculations play an important role in the design of nanoelectronic field-effect transistors (FETs), but their computational intensity is the primary challenge. To address this, we developed a physics-knowledge-integrated neural network framework that directly predicts quantum transport current-voltage curves for gate-all-around FETs. This model significantly accelerates FET design optimization while maintaining the density-functional theory–level accuracy. By integrating key physical parameters of the channel materials, our model achieves a mean absolute error as low as 0.39. In particular, 98% of the current prediction residuals are within one order of magnitude, even with a limited training dataset. The differentiable nature of the neural network allows for automatic differentiation analysis, providing interpretable insights into our model. This ensures that the model has successfully learned quantum transport physics, thereby enhancing its reliability. Using our model, we efficiently identified symmetric p-type gate-all-around FETs with performance comparable to n-type ones, which are crucial for developing homogeneous complementary metal-oxide semiconductor circuits. This work provides an effective and reliable method for rapidly screening and optimizing FET designs, paving the way for accelerating the design process of next-generation electronic devices.

Amplitude-modulation atomic force microscopy (AM-AFM) measures nanoscale surface structures by detecting changes in the cantilever oscillation amplitude, contributing to materials research. AM-AFM can nondestructively observe fragile molecules, such as biomolecules, even while the probe is in intermittent contact with the sample. However, the interaction force estimated from experimental amplitude values is significantly greater than actual molecular binding forces, despite the successful visualization of molecular dynamics, raising a fundamental question about force quantification. Here, we formulate a quantitative force conversion equation for arbitrary driving frequencies. A comprehensive theoretical analysis reveals that, when the cantilever is excited at the resonance slope, the conventional equation overestimates the actual force by approximately five times since it is valid only for excitation at the resonance frequency. This mathematical framework is validated through simulations and experiments, offering new insights into AM-AFM force estimation. The findings provide a crucial toolset for accurate yet easy-to-use force quantification, enhancing the reliability of practical AM-AFM applications in materials and biomolecular research.

Atomically thin films and surfaces exhibit many distinctive two-dimensional electronic properties that are absent in bulk crystals. In situ microscale multiprobe measurements have been utilized as an effective method to identify the electrical conductivity of such thin films and surfaces. Precise determination of multiprobe positions is crucial for accurate characterization of the conductance. However, traditional methods that use microscopes for determining multiprobe positions often impose significant constraints on experimental setups. In some cases, installing a microscope is not even feasible. Therefore, in this study, we propose a novel method to determine probe positions using electrical signals from the probes. This method enables precise determination of probe positions using a reference sheet and reference probes, even at low or high temperatures and under ultrahigh-vacuum or high-pressure conditions. The proposed method simplifies the integration of microscale multiprobe measurement systems into various devices, thereby advancing research on thin films and surfaces.

The detection of narrow and high-amplitude optical resonances in atomic cells is of crucial importance for the development of compact and high-stability lasers or vapor-cell optical references. In this work, using monochromatic light and appropriate polarization settings for the counterpropagating pump and probe beams, we demonstrate the detection of enhanced-absorption sub-Doppler resonances on the $D_1$ line of the $\mathrm{Rb}$ atom. We report a theoretical model showing that the Zeeman coherence induced between magnetic sublevels—especially in the $F\to F^{\prime }=F-1$ systems, with $F$ and $F^{\prime }$ being the hyperfine quantum numbers of the ground and excited states, respectively—plays a key role in the observed enhanced-absorption process. The theoretically predicted behavior matches the experimental observations well. The impact of light polarization, laser intensity, magnetic field, and cell temperature on the Doppler-free resonance features is experimentally investigated. For application, two identical diode lasers are frequency-stabilized onto enhanced-absorption sub-Doppler resonances. The fractional frequency stability of the laser beatnote is measured to be $1.8\times {10}^{-12}$ at $1\mathrm{s}$ and $8.4\times {10}^{-12}$ at ${10}^4\mathrm{s}$. These results demonstrate the potential of this scheme for the implementation of a compact or even chip-scale optical frequency reference, which might find applications in instrumentation, navigation, and metrology.

We study surface acoustic waves (SAWs) in yttrium iron garnet (YIG)/zinc oxide (ZnO) heterostructures, comparing the results of a computationally lightweight analytical model with time-resolved microfocused Brillouin light scattering ($\text{μ}$-BLS) data. Interdigital transducers (IDTs), with operational frequencies in the gigahertz regime, were fabricated on 50-nm and 100-nm thin films of YIG prior to sputter deposition of 830-nm and 890-nm films of piezoelectric ZnO. We find good agreement between our analytical model and $\text{μ}$-BLS data of the IDT frequency response and SAW group velocity, with clear differentiation between the Rayleigh-like and Sezawa-like modes. Finally, nonreciprocal coupling between SAWs and spin waves (SWs) is shown. This work paves the way for a detailed study of the interaction between SAWs and SWs in low SW damping YIG, with the possibility of a method for future energy-efficient SW excitation.

Traditionally, the excitation of effective surface plasmon polaritons (ESPPs) in rectangular waveguides (RWGs) relies on gradient-transition structures to facilitate momentum and impedance matching between the transverse electric ${\mathrm{TE}}_{10}$ and ESPP modes. However, the inherently large and bulky nature of these transitions imposes significant limitations on the practical implementation of ESPP-based functional devices. In this work, we propose a novel transition-free ultrawideband ESPP waveguide filter that enhances the ESPP mode excitation through improved wideband momentum matching. By eliminating the bulky transition structures, the proposed design achieves significant miniaturization while maintaining superior in-band performance. A simple and effective method for extracting the characteristic impedance of ESPPs is introduced, enabling further optimization of the passband response via impedance matching within the transition-free framework. Compared with conventional ESPP- or spoof surface plasmon polariton (SSPP)-based filters that rely on gradient transitions, the proposed design offers a substantial reduction in the overall length without compromising performance. As a proof of concept, a prototype filter centered at 9.3 GHz was fabricated and tested, achieving a compact length of only $0.981{\lambda }_0$, a fractional bandwidth of 58%, a shape factor of 1.064, and an insertion loss of just 0.25 dB. These results establish a robust foundation for the practical application of compact and efficient ESPP devices.

The noise-biased Kerr-cat qubit is an attractive candidate for fault-tolerant quantum computation; however, its initialization faces challenges due to the squeezing pump-induced frequency shift. Here we propose and demonstrate a dynamic compensation method to mitigate the effect of pump-induced frequency shift during the Kerr-cat qubit initialization. Using a nonlinearity-engineered multiloop superconducting quantum interference device, we realize a stabilized Kerr-cat qubit and validate the advantages of the dynamic compensation method by increasing the initialization fidelity from 57% to 78%, with a projected fidelity of 91% after exclusion of state preparation and measurement errors. Our results not only advance the practical implementation of Kerr-cat qubits, but also provide valuable insights into the fundamental adiabatic dynamics of these systems. This work is valuable for scalable quantum processors that leverage the noise-biased properties of Kerr-cat qubits.

Integrating two-dimensional (2D) materials into circuit quantum electrodynamics (cQED) devices is an emerging field in recent years. This integration not only facilitates the exploration of potential applications in quantum information processing but also enables the study of material’s fundamental properties using microwave techniques. While most studies employ 2D coplanar architectures with scalability potential, three-dimensional (3D) cavity-based cQED devices, due to their simpler design, offer the advantage of a quicker turnaround to probe the composite Josephson junctions (JJs). Here, we construct the first flux-tunable, 3D cavity-compatible superconducting quantum circuit based on 2D materials, featuring a graphene superconducting quantum interference device (SQUID) shunted by a capacitor that is accessible by both dc and microwave probes. We have shown how flux-modulated cavity frequency can be linked to the SQUID critical current under the influence of Fraunhofer’s pattern. In addition, we extracted the symmetry information of the SQUIDs based on dc analysis, and correlated this with the flux-modulated cavity frequency observed in microwave measurements. Our platform can extend to topological materials, holding the prospect of establishing valid topological JJs with a dc probe while allowing a fast microwave probe to avoid quasiparticle poisoning.

Chirality plays a crucial role in the helicity mismatch between surface acoustic waves and magnetic spin waves, leading to nonreciprocal transmission of acoustic power for coupled magnetoacoustic modes. Acoustic modes with both longitudinal and shear strain exhibit elliptical particle displacements, making them chiral, and different acoustic modes can exhibit different helicities of this elliptical particle displacement. Here, we study chiral acoustic modes with different helicities supported on the same piezoelectric platform and their interaction with magnetic spin waves. Our study demonstrates that the nonreciprocal transmission of acoustic power is driven by the helicity mismatch effect and, specifically, that the handedness of the nonreciprocity is based on whether the surface acoustic wave has retrograde (Rayleigh mode) or prograde (Sezawa mode) elliptical particle displacement with respect to the propagation direction. We found the transmission nonreciprocity to be significant, with 7.3 dB/mm for the retrograde particle displacement (Rayleigh mode at 2.358 GHz) and 3.3 dB/mm for prograde particle displacement (Sezawa mode at 3.112 GHz). This work highlights that piezoelectric platforms can be engineered to support acoustic modes with opposite helicities to enable frequency-selective nonreciprocal radiofrequency and microwave components, such as isolators and circulators, through coupled acoustic spin wave interactions.

Quantum secret sharing (QSS) plays a pivotal role in multiparty quantum communication, ensuring the secure distribution of private information among multiple parties. However, the security of QSS schemes can be compromised by attacks exploiting imperfections in measurement devices. Here, we propose a reconfigurable approach to implement QSS based on measurement-device-independent (MDI) principles, utilizing linear two-photon Bell-state analysis. By employing single-qubit conjugate operations for encoding private classical information, our approach offers reconfigurability, allowing for the inclusion of additional parties without sacrificing efficiency. Furthermore, we demonstrate the robust security of our MDI QSS scheme against intereavesdropping by dishonest participants and establish lower bounds for secure communication among three legitimate parties. This work presents a flexible configuration for implementing multiparty secure quantum communication with imperfect measurement devices and represents a significant advancement in the development of secure quantum communication technologies.

Space-based gravitational wave detection projects require stringent temperature stability of core payloads in the frequency domain. To facilitate thermal design iterations in the preliminary stage, it is essential to establish thermal disturbance requirements for different thermal disturbance sources surrounding the core payloads at the outset of the mission. A significant challenge in this process is determining the impact of noise sources on the core payloads when their characteristics are not fully known. In this paper, we investigate the influence of different potential noise sources on the inertial sensors within the core area of the TianQin project. Our process involves transforming the mechanical construction model into a thermal mathematical model and deriving the system’s transfer function matrix by a linear control methods. This matrix enables an analysis of the effects of thermal disturbance sources on the inertial sensor’s temperature stability within a bandwidth from $0.01\mathrm{mHz}$ to $0.1\mathrm{Hz}$. Additionally, thermal stability requirements for these noise sources at $0.1$ and $1\mathrm{mHz}$ are listed through the inertial sensor’s requirement, providing meaningful guidance for the subsequent thermal design of TianQin. The analytical process, demonstrated for TianQin, can be applied to other space missions requiring stringent temperature stability in their core payload during preliminary stages.

The range and velocity of a moving object can be ascertained using the sensing technique known as light detection and ranging (lidar). It has recently been suggested that quantum lidar, which uses entangled states of light, can enhance the capabilities of lidar. Entangled pulsed light is used in prior quantum lidar approaches to assess both range and velocity at the same time using the time of flight and Doppler shift. However, the detection of entangled pulsed light is often inefficient and constrained by the temporal resolution of the detectors. Here, we investigate a quantum lidar utilizing a linear interferometer operating on a frequency-modulated continuous wave (FMCW) instead of pulses. Our findings demonstrate that the quantum FMCW lidar enables simultaneous measurements of range and velocity with quantum-enhanced accuracy and resolution, as well as superresolution phase imaging. Through self-heterodyne detection with a linear optical design, the signals of the quantum FMCW lidar with entangled photon pair can be efficiently carried out electronically by down-converting the optical signal to the microwave region. As a result, it is better suited for practical implementations.

Sound waves have consistently served as vital carriers of information in the physical world. However, in the realms of hydroacoustics and medical ultrasound, the impedance mismatch between the solid and liquid poses significant challenges, resulting in energy dissipation that hinders the effective transmission of information. Hence, achieving underwater sound transparency holds tremendous significance for advancing underwater acoustic communication technology and fostering innovations in the research and development of medical ultrasound equipment. This research endeavor leverages multimode coupling to transcend the limitations of previous narrow-band sound transparency designs. Confirmed by experiments, this work achieves broadband sound transparency spanning from $170$ to $230\mathrm{kHz}$. Furthermore, leveraging the abundance of geometric parameters and the flexibility of degrees of freedom, we introduce a dual broadband design, which exhibits dual broadband sound transparency with passbands of $280–350\mathrm{kHz}$ and $450–510\mathrm{kHz}$. Crucially, our research serves as a stepping stone towards realizing broadband acoustic underwater metasurfaces, thereby paving the way for advancements in ultrasonic imaging and underwater acoustic communications.

Harnessing in-plane acoustic radiation torque exerted by orbital angular momentum (OAM) of two-dimensional (2D) vortex beams to manipulate the rotation of objects has become a burgeoning field and garnered increased attention in recent years, yet the existing mechanisms generally have to rely on a closed system to prevent energy leakage and multiple sources when constructing the helical wave front. Here, we present the design and experimental demonstration of a compact on-chip ultrasonic motor built using a monolayered acoustic metasurface with no need for a sophisticated phased array or enclosed 2D system. By decorating an open surface with resonance-coupled ultrathin structures and manipulating its in-plane refractive index based on the theoretically derived dispersion relation, we convert the linear momentum emitted from a single source in free space to the surface-bounded sonic OAM, which serves as a driving torque and enables precise rotation of a targeted object in a high efficiency and contactless way. Numerical and experimental results demonstrate the effective twisting of surface momentum and exceptional mechanical performance of the ultrasonic motor for rotating the rotor. This compact ultrasonic motor pioneers new pathways for the design of planar vortex devices in an open surface system and may find important on-chip applications in diverse scenarios such as biological centrifugation.