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Adiabatic processes are useful in quantum control, but they are slow. A way around this is to exploit shortcuts to adiabaticity, which can speed things up — for instance, by boosting stimulated Raman adiabatic passage. Adiabatic processes are useful for quantum technologies 1 , 2 , 3 but, despite their robustness to experimental imperfections, they remain susceptible to decoherence due to their long evolution time. A general strategy termed shortcuts to adiabaticity 4 , 5 , 6 , 7 , 8 , 9 (STA) aims to remedy this vulnerability by designing fast dynamics to reproduce the results of a slow, adiabatic evolution. Here, we implement an STA technique known as superadiabatic transitionless driving 10 (SATD) to speed up stimulated Raman adiabatic passage 1 , 11 , 12 , 13 , 14 in a solid-state lambda system. Using the optical transitions to a dissipative excited state in the nitrogen-vacancy centre in diamond, we demonstrate the accelerated performance of different shortcut trajectories for population transfer and for the initialization and transfer of coherent superpositions. We reveal that SATD protocols exhibit robustness to dissipation and experimental uncertainty, and can be optimized when these effects are present. These results suggest that STA could be effective for controlling a variety of solid-state open quantum systems 11 , 12 , 13 , 14 , 15 , 16 .

The relative contribution of adiabatic and non‐adiabatic processes to electron heating across collisionless shocks remains an open question. We analyze the evolution of suprathermal electrons across 310 quasi‐perpendicular shocks with Alfvénic Mach numbers in the normal‐incidence frame MA−NIF$\\left({M}_{A-NIF}\\right)$ranging from 1.7 to 48, using in situ measurements of Earth's bow shock by the Magnetospheric Multiscale (MMS) spacecraft. We introduce a novel non‐adiabaticity measure derived from the electron distribution function and based on Liouville's theorem. Our results reveal, for the first time, that the electron heating mechanism is governed by the Alfvénic Mach number in the de Hoffman‐Teller frame MA−HT$\\left({M}_{A-HT}\\right)$ , with a transition from predominantly adiabatic to non‐adiabatic heating occurring at MA−HT≳30${M}_{A-HT}\\gtrsim 30$ . Furthermore, by examining the spectral index of the suprathermal electron distribution, we find that for shocks exhibiting dominant non‐adiabatic electron dynamics, the observed electron heating is consistent with the predictions of the stochastic shock drift acceleration (SSDA) mechanism. Plain Language Summary Understanding how electrons get heated across shock waves in space is a challenging scientific question. These shocks can heat electrons through different processes: some involve smooth, gradual changes (adiabatic), while others involve more chaotic interactions (non‐adiabatic). In this study, we looked at data from 310 shock events near Earth using the Magnetospheric Multiscale (MMS) spacecraft, focusing on shocks with a normal vector almost perpendicular to the direction of the magnetic field. We developed a new way to measure how much of the heating is due to non‐adiabatic processes by studying the patterns in how the electrons are distributed in energy. Our findings show that the way electrons are heated is mainly controlled by a dimensionless parameter called the Alfvénic Mach number, which describes how fast the shock is moving compared to a specific speed in the plasma, in a particular frame of reference (the de Hoffman‐Teller frame). We discovered that when this Mach number is above about 30, the heating changes from being mostly adiabatic to mostly non‐adiabatic. Additionally, we found that when non‐adiabatic heating is dominant, it matches well with a known process called stochastic shock drift acceleration (SSDA). Key Points We analyze electron heating across 310 quasi‐perpendicular shocks observed by MMS We use a Liouville mapping technique to show the electron heating mechanism is controlled by the Mach number in the de Hoffmann‐Teller frame We find that electron heating at shocks with dominant nonadiabatic dynamics aligns with the stochastic shock drift acceleration mechanism

A digitized approach to adiabatic quantum computing, combining the generality of the adiabatic algorithm with the universality of the digital method, is implemented using a superconducting circuit to find the ground states of arbitrary Hamiltonians. A demonstration of quantum computing Adiabatic quantum computers are analogue machines that, with the help of quantum tunnelling, slowly evolve from a simple input to the desired, more complicated output. Although adiabiatic quantum computers can be very fast at specific tasks, they are limited by noise and errors that cannot be corrected during the computation. In contrast, universal quantum computers are digital devices that use logic gates and allow for error correction. Here, Rami Barends et al . combine the advantages of adiabiatic and universal quantum computers by digitizing an adiabiatic quantum computation. This approach allows for encoding non-stoquastic Hamiltonians, which are crucial for simulating physical and chemical systems with interacting fermions. Quantum mechanics can help to solve complex problems in physics 1 and chemistry 2 , provided they can be programmed in a physical device. In adiabatic quantum computing 3 , 4 , 5 , a system is slowly evolved from the ground state of a simple initial Hamiltonian to a final Hamiltonian that encodes a computational problem. The appeal of this approach lies in the combination of simplicity and generality; in principle, any problem can be encoded. In practice, applications are restricted by limited connectivity, available interactions and noise. A complementary approach is digital quantum computing 6 , which enables the construction of arbitrary interactions and is compatible with error correction 7 , 8 , but uses quantum circuit algorithms that are problem-specific. Here we combine the advantages of both approaches by implementing digitized adiabatic quantum computing in a superconducting system. We tomographically probe the system during the digitized evolution and explore the scaling of errors with system size. We then let the full system find the solution to random instances of the one-dimensional Ising problem as well as problem Hamiltonians that involve more complex interactions. This digital quantum simulation 9 , 10 , 11 , 12 of the adiabatic algorithm consists of up to nine qubits and up to 1,000 quantum logic gates. The demonstration of digitized adiabatic quantum computing in the solid state opens a path to synthesizing long-range correlations and solving complex computational problems. When combined with fault-tolerance, our approach becomes a general-purpose algorithm that is scalable.

The tropopause represents a central feature of the atmospheric vertical structure, marking the transition between the troposphere and stratosphere. While common definitions rely on quantities conserved under adiabatic changes, diabatic effects, resulting from radiation, cloud processes or turbulence are also decisive for the tropopause structure. Therefore, we propose a new definition based on the vertical gradient of the relative humidity with respect to ice (RHi). RHi is the key variable for ice cloud formation and incorporates both diabatic and adiabatic processes. Based on high-resolution radiosonde data, we can show that our RHi-GT-based definition is generally consistent with, and often provides a clearer characterization than the thermal tropopause. This is not only evident in individual vertical profiles, but also when looking at statistics of many profiles with a tropopause-relative height axis. Last but not least, the robust and simple calculation of our definition makes it an ideal tool for studies involving the tropopause.

East Antarctica has experienced significant positive temperature anomalies during winter 2018, with Zhongshan (ZS) station recording its highest winter average temperature since 2008 and fourth highest since its establishment in 1989. This study employs observational data and ERA5 reanalysis to diagnose the phenomenon, revealing that temperature anomalies at 300 hPa are mainly driven by advection and adiabatic processes, which is the second highest recorded from 2000 to 2020. However, diabatic process are significantly important at 700 hPa, being the third highest during the period. The reduction in sea ice, combined with enhanced sinking motion and increased sea‐air temperature difference, together contributes to the variations of diabatic heating. The increased precipitation, exceeding the historical average by 100% along the southwestern shore of Prydz Bay, further induces localized warming. The increased atmospheric pressure associated with the negative Southern Annular Mode phase is the primary cause influencing the advection, adiabatic, and diabatic processes. Plain Language Summary Since 2015, East Antarctica has generally warmed due to a significant reduction in sea ice. However, a systematic understanding of this warming remains lacking. This study investigates the significant positive temperature anomalies observed in East Antarctica during the winter of 2018, when Zhongshan station records its highest winter average temperature since 2008 and fourth highest since its establishment in 1989. Observational data and ERA5 reanalysis are employed to analyze the mechanism behind the phenomenon, revealing strong temporal and spatial correlations between pressure and temperature. The positive temperature anomalies at 300 hPa are mainly due to warm air masses from northerly winds and air compression from increased downward winds, both influenced by pressure anomalies. However, temperature variations at lower altitudes are significantly influenced by heat transfer from ocean to atmosphere, with decreased sea ice, combined with enhanced vertical motion and sea‐air temperature deference, together contributing to the transfer. The increased precipitation further induces localized warming through latent heat release. The increased atmospheric pressure associated with the negative Southern Annular Mode phase is the primary cause influencing the local circulation and sea ice, eventually leading the anomalies of advection, adiabatic, and diabatic processes. Key Points East Antarctica has experienced significant positive temperature anomalies during the winter of 2018, especially at lower altitudes Temperature anomalies at 300 hPa are mainly due to advection and adiabatic processes, while diabatic effects are most important at 700 hPa Anomalies of sea ice, winds and precipitation, induced by negative Southern Annular Mode phase, together contribute to the positive temperature anomalies

The increasing frequency of heatwaves over East Asia (EA) is impacting agriculture, water management, and people’s livelihood. However, the effect of humidity on high-temperature events has not yet been fully explored. Using observations and future climate change projections conducted with the latest generation of Earth System models, we examine the mechanisms of dry and moist heatwaves over EA. In the dry heatwave region, anticyclonic circulation has been amplified after the onset of heatwaves under the influence of the convergence of anomalous wave activity flux over northern EA, resulting in surface warming via adiabatic processes. In contrast, the moist heatwaves are triggered by the locally generated anticyclonic anomalies, with the surface warming amplified by cloud and water vapor feedback. Model simulations from phase six of the Coupled Model Intercomparison Project projected display intensification of dry heatwaves and increased moist heatwave days in response to projected increases in greenhouse gas concentrations.

A new turbulent kinetic energy (TKE)-based moist eddy-diffusivity mass-flux (EDMF) vertical turbulence mixing scheme (EDMF-TKE) is developed, where the nonlocal transport by large turbulent eddies is represented by a mass-flux (MF) scheme while the local transport by small turbulent eddies is represented by an eddy-diffusivity (ED) scheme, which is given by a function of a prognostic TKE. In the scheme, an MF approach is employed for the stratocumulus-top-driven downdrafts as well as for the thermals in the daytime unstable boundary layer. The scheme includes parameterizations for enhanced buoyancy due to moist adiabatic processes in condensation and for TKE interaction with cumulus convection. A scale-aware parameterization is proposed for the grid sizes where the large turbulent eddies are partially resolved. The single-column model (SCM) tests show that both the EDMF-TKE and the current operational NCEP GFS hybrid EDMF scheme (EDMF-CTL) simulate a daytime dry-convective boundary layer well and agree with a benchmark large-eddy simulation (LES). For a marine stratocumulus-topped boundary layer case, the EDMF-TKE better simulates the liquid water and wind speed profiles than the EDMF-CTL compared to the LES. For a stable boundary layer (SBL) case, the EDMF-TKE also agrees better with the LES than the EDMF-CTL, although it tends to produce a deeper SBL compared to the LES. On the other hand, three-dimensional medium-range forecast experiments show that the EDMF-TKE slightly improves forecast skill in the 500-hPa height anomaly correlation and wind vector, while it has a neutral impact on precipitation forecasts over the continental United States.

By using transitionless quantum driving algorithm (TQDA), we present an efficient scheme for the shortcuts to the holonomic quantum computation (HQC). It works in decoherence-free subspace (DFS) and the adiabatic process can be speeded up in the shortest possible time. More interestingly, we give a physical implementation for our shortcuts to HQC with nitrogen-vacancy centers in diamonds dispersively coupled to a whispering-gallery mode microsphere cavity. It can be efficiently realized by controlling appropriately the frequencies of the external laser pulses. Also, our scheme has good scalability with more qubits. Different from previous works, we first use TQDA to realize a universal HQC in DFS, including not only two noncommuting accelerated single-qubit holonomic gates but also a accelerated two-qubit holonomic controlled-phase gate, which provides the necessary shortcuts for the complete set of gates required for universal quantum computation. Moreover, our experimentally realizable shortcuts require only two-body interactions, not four-body ones, and they work in the dispersive regime, which relax greatly the difficulty of their physical implementation in experiment. Our numerical calculations show that the present scheme is robust against decoherence with current experimental parameters.

The continuous, moored observation revealed significant variability in the strength of the Atlantic meridional overturning circulation (AMOC). The cause of such AMOC variability is an extensively studied subject. This study focuses on the short-term variability, which ranges up to seasonal and interannual time scales. A mechanism is proposed from the perspective of ocean water redistribution by layers. By offering explanations for four phenomena of AMOC variability in the subtropical and tropical oceans (seasonality, meridional coherence, layered-transport compensation as observed at 26.5°N, and the 2009/10 downturn that occurred at 26.5°N), this mechanism suggests that the short-term AMOC variabilities in the entire subtropical and tropical regions are governed by a basinwide adiabatic water redistribution process, or the so-called sloshing dynamics, rather than diapycnal processes.

While climate models project that Greenland ice sheet (GrIS) melt will continue to accelerate with climate change, models exhibit limitations in capturing observed connections between GrIS melt and changes in high-latitude atmospheric circulation. Here we impose observed Arctic winds in a fully-coupled climate model with fixed anthropogenic forcing to quantify the influence of the rotational component of large-scale atmospheric circulation variability over the Arctic on the temperature field and the surface mass/energy balances through adiabatic processes. We show that recent changes involving mid-to-upper-tropospheric anticyclonic wind anomalies – linked with tropical forcing – explain half of the observed Greenland surface warming and ice loss acceleration since 1990, suggesting a pathway for large-scale winds to potentially enhance sea-level rise by ~0.2 mm/year per decade. We further reveal fingerprints of this observed teleconnection in paleo-reanalyses spanning the past 400 years, which heightens concern about model limitations to capture wind-driven adiabatic processes associated with GrIS melt. Here, the authors highlight that a better representation of large-scale wind-driven warming processes in climate models has potential for lessening sea-level rise projection uncertainties associated with Greenland ice sheet melt.