We present a novel experimental approach to retrieve both the ionization and return times in high harmonic generation from the spectral phases of the radiation generated by a two-color femtosecond field. By performing a detailed characterization of the phases as both the ratio and delay between the …

[Phys. Rev. Lett. 136, 193201] Published Thu May 14, 2026

Recent quench experiments on ultracold atoms in optical cavities provide a clean platform for studying how long-range interactions in atomic media structure their nonequilibrium dynamics. Motivated by these experiments, we provide a theoretical analysis of the quench instabilities that lead to the f…

[Phys. Rev. Lett. 136, 193401] Published Thu May 14, 2026

We report the first experimental observation of discrete time crystal phases and crystallites in an actively mode-locked semiconductor laser. By tuning either the bias current or the modulation frequency, the system undergoes a spontaneous symmetry-breaking transition from the harmonically mode-lock…

[Phys. Rev. Lett. 136, 193801] Published Thu May 14, 2026

Continuous time crystals (CTCs) are nonequilibrium phases that spontaneously break continuous time-translation symmetry to sustain persistent oscillations under time-invariant driving. Here we report the first realization of CTC in a photorefractive carrier-transport system, using iron-doped lithium…

[Phys. Rev. Lett. 136, 193802] Published Thu May 14, 2026

We report on a microscopic theory of quantum friction. Our approach investigates the interplay between the dispersive response and the relative center-of-mass motion of two ground-state atoms. This coupling yields a quantum force, which can be expressed as a power series in the velocity. The signifi…

[Phys. Rev. Lett. 136, 193601] Published Tue May 12, 2026

Rotation is a natural tool in ultracold gases to break time-reversal symmetry, yet its impact on the collective excitations of supersolids remains largely unexplored. We show theoretically that tuning the rotation frequency, rather than the interparticle interactions, can trigger the superfluid-to-s…

[Phys. Rev. Lett. 136, 183401] Published Fri May 08, 2026

An experiment shows that geometric phase of Pancharatnam-Berry metasurfaces can be preserved while their intrinsic spin duality is deliberately broken.

[Phys. Rev. Lett. 136, 183805] Published Fri May 08, 2026

Airy wave functions are associated with one of the simplest scenarios in wave mechanics: a quantum bouncing ball. In other words, they are the eigenstates of the time-independent Schrödinger equation with a linear potential. In the domain of optics, laser beams that are spatially shaped as Airy func…

[Phys. Rev. Lett. 136, 183804] Published Wed May 06, 2026

Non-Hermitian Hamiltonians with complex eigenenergies are useful tools for describing the dynamics of open quantum systems. In particular, parity and time ($\mathcal{P}\mathcal{T}$) symmetric Hamiltonians have generated interest due to the emergence of exceptional-point degeneracies, where both eigenenergies and eigenvec…

[Phys. Rev. Lett. 136, 183601] Published Tue May 05, 2026

Coupling a film of enriched ${}^{57}$Fe to a surface acoustic wave produces a comb of absorption sidebands in the Mossbauer spectrum, consistent with coherent phase modulation of the nuclear transition.

[Phys. Rev. Lett. 136, 183801] Published Tue May 05, 2026

Intense light fields with spatiotemporally structured wave fronts open new avenues for exploring nonlinear light-matter interactions in ultrafast spectroscopy and photonic technologies. Here, we report the observation of geometric phase induced spin-orbit interaction (SOI) in high harmonic generatio…

[Phys. Rev. Lett. 136, 183802] Published Tue May 05, 2026

Quasimonochromatic (QM) coherent extreme ultraviolet (EUV) pulses have emerged as crucial tools for spectroscopic and imaging applications. Such pulses could be obtained by selectively enhancing a specific harmonic order in high-harmonic generation (HHG). However, it is still challenging to directly…

[Phys. Rev. Lett. 136, 183803] Published Tue May 05, 2026

We theoretically and experimentally investigate spontaneous self-organization in a conservative (Hamiltonian) turbulent wave system, operating far from thermodynamic equilibrium. Our system is governed by two coherently coupled nonlinear Schrödinger equations, describing the polarization evolution o…

[Phys. Rev. Lett. 136, 173801] Published Wed Apr 29, 2026

Conventional femtosecond coherent laser spectroscopy predominantly focuses on the temporal phase coherence through time- or frequency-resolved methods. In this Letter, we suggest an alternative experimental framework based on spatial phase coherence. The intrinsic spectral dispersion of wave vectors…

[Phys. Rev. Lett. 136, 163801] Published Wed Apr 22, 2026

Attosecond soft-X-ray pump-probe spectroscopy of xenon and krypton atoms reveals two previously unobserved dynamical features in xenon that are inconsistent with lifetimes inferred from energy-domain measurements.

[Phys. Rev. Lett. 136, 163201] Published Mon Apr 20, 2026

Manipulating the quantum noise of continuous-wave lasers through squeezing has reshaped optical interferometry. However, progress in optical frequency comb interferometry with pulsed squeezed sources has been limited, despite the role of frequency combs in ultraprecise optical metrology. Here, we in…

[Phys. Rev. Lett. 136, 163601] Published Mon Apr 20, 2026

High-precision clocks based on quantum systems will work in a regime where a quantum description of proper time might be necessary.

[Phys. Rev. Lett. 136, 163602] Published Mon Apr 20, 2026

Metastable atomic qubits are a highly promising platform for the realization of quantum computers, owing to their scalability and the possibility of converting leakage errors to erasure errors midcircuit. Here, we demonstrate and characterize a high-fidelity quantum gate set for the metastable fine-…

[Phys. Rev. Lett. 136, 153602] Published Thu Apr 16, 2026

We present strong-field photoelectron holography measurements of hydrogen chloride (HCl) that resolve subcycle dynamics in two ionization channels associated with the HOMO and HOMO-1 orbitals. The holograms in the photoelectron momentum distributions show different cutoffs and interference fringes t…

[Phys. Rev. Lett. 136, 153202] Published Wed Apr 15, 2026

Snapshot measurements of cold-atom gases reveal hidden spin correlations that could force an update of some superconductivity theories.

[Phys. Rev. Lett. 136, 153402] Published Wed Apr 15, 2026

Although Rydberg atoms have shown promise for use in novel types of radio frequency (rf) receivers, they have generally not been considered phase sensitive without the use of closed-loop interferometry or auxiliary rf fields. Here, we show that the high coherency of a narrow-linewidth three-photon l…

[Phys. Rev. Lett. 136, 153201] Published Tue Apr 14, 2026

We report the numerical observation of a far-from-equilibrium equation of state (EOS) in the Gross-Pitaevskii (GP) model. We first show that the momentum distribution of the turbulent cascade is well described by wave-turbulent kinetic theory in the appropriate limits. Calculating the energy and par…

[Phys. Rev. Lett. 136, 153401] Published Tue Apr 14, 2026

When a photon traverses a cloud of atoms without scattering, how much time does it spend as an atomic excitation? To address this question, we used the cross-Kerr effect to weakly probe the degree of atomic excitation caused by a transmitted resonant “signal” photon by measuring the phase shift indu…

[Phys. Rev. Lett. 136, 153601] Published Mon Apr 13, 2026

We report on measurements of extreme ultraviolet (EUV) radiation from highly charged gold ions in laser-produced plasma to investigate the quantum electrodynamics (QED) effects, Breit interaction, and electron correlation (EC) effects which play a crucial role in determining the energy levels of hig…

[Phys. Rev. Lett. 136, 143201] Published Fri Apr 10, 2026

Wavefront distortions are a leading source of systematic uncertainty in light-pulse atom interferometry, limiting absolute measurements of gravitational acceleration at the $30\mathrm{nm}/{\mathrm{s}}^2$ level. Here, we demonstrate in situ spatially resolved measurement of the interferometer phase in a Mach-Zehnder atom…

[Phys. Rev. Lett. 136, 143402] Published Fri Apr 10, 2026

The electromagnetic field of standing-wave or ring cavities induces a spatially modulated, infinite-range interaction between atoms in an ultracold Fermi gas, with a single wavelength comparable to the Fermi length. This interaction has no analog in other systems of itinerant particles and has so fa…

[Phys. Rev. Lett. 136, 143403] Published Fri Apr 10, 2026

To date, realization of a continuous-wave active atomic clock has been elusive, primarily due to parasitic heating from spontaneous emission while repumping the atoms. Here, we propose a solution to this problem by replacing the random emission with coupling to an auxiliary cavity, making repumping …

[Phys. Rev. Lett. 136, 143803] Published Thu Apr 09, 2026

Precise spectroscopy of a simple molecular ion opens a new path toward stringent tests of quantum electrodynamics.

[Phys. Rev. Lett. 136, 143002] Published Wed Apr 08, 2026

Breaking time-reversal symmetry in integrated photonics without magnetic fields remains a fundamental challenge. We demonstrate phonon-induced nonreciprocity through direct lifting of forward-backward mode degeneracy in microring resonators. Coherent acousto-optic coupling generates differential AC …

[Phys. Rev. Lett. 136, 143802] Published Wed Apr 08, 2026

The ability to control solid-state quantum emitters is fundamental to advancing quantum technologies. The performance of these systems is fundamentally governed by their spin-dependent photodynamics, yet conventional control methods using cavities offer limited access to key nonradiative processes. …

[Phys. Rev. Lett. 136, 143001] Published Mon Apr 06, 2026

A new microscope captures how atoms rearrange themselves when they are illuminated inside an optical cavity.

[Phys. Rev. Lett. 136, 143401] Published Mon Apr 06, 2026

Motivated by the importance of dispersive readout in quantum technology, we study a prototypical dispersive readout setup that is probed by a squeezed vacuum in a time-reversal-symmetric fashion. To this end, we develop a full-counting-statistics framework for dispersive readout and analyze its meas…

[Phys. Rev. Lett. 136, 143601] Published Mon Apr 06, 2026

Non-line-of-sight (NLOS) imaging aims to recover hidden scenes outside the direct line of sight, holding great promise for broad applications. Despite notable advancements, current methods are restricted to the manipulation of temporal or spatial degree of light. Here, we propose and demonstrate pol…

[Phys. Rev. Lett. 136, 143801] Published Mon Apr 06, 2026

The use of nuclear spins as physical sensing systems is disadvantaged by their low signal responsivity, particularly when compared to sensing techniques based on electron spins. This primarily results from the small nuclear gyromagnetic ratio and the difficulties in achieving high spin polarization.…

[Phys. Rev. Lett. 136, 133201] Published Thu Apr 02, 2026

Researchers have improved trapping of polyatomic molecules while also controlling their collisions—two important advances for ultracold polyatomic molecular physics.

[Phys. Rev. Lett. 136, 133402] Published Wed Apr 01, 2026

Higher-order topological photonic systems typically host corner states that are exponentially localized. Here we uncover a distinct regime of uniformly delocalized higher-order topological modes, emerging from the interplay of multiple spatially varying Dirac mass terms under chiral symmetry. These …

[Phys. Rev. Lett. 136, 133801] Published Tue Mar 31, 2026

The superfluid fraction of a 2D Bose-Einstein condensate is experimentally determined for the first time.

[Phys. Rev. Lett. 136, 133401] Published Mon Mar 30, 2026

The question of whether interactions can break dynamical localization in quantum kicked rotor systems has been the subject of a long-standing debate. Here, we introduce an extended mapping from the kicked Lieb-Liniger model to a high-dimensional lattice model and reveal universal features: on-site p…

[Phys. Rev. Lett. 136, 123402] Published Fri Mar 27, 2026

The emergence of breathing solitons in mode-locked lasers presents a fundamental challenge for the theoretical modeling of mode locking, with the mechanisms underlying below- and above-threshold breathing solitons, and the origins of their distinct nonlinear dynamics, remaining poorly understood. He…

[Phys. Rev. Lett. 136, 123801] Published Fri Mar 27, 2026

Understanding the dissociation of multiply charged molecules is crucial yet challenging due to complex multibody correlations and nonadiabatic dynamics. Conventional ab initio molecular dynamics simulations commonly struggle to capture excited electronic states and intricate electron-nuclear couplin…

[Phys. Rev. Lett. 136, 123202] Published Wed Mar 25, 2026

We measure strong field ionization of cesium atoms, observing a robust feature near $2U_{\mathrm{p}}$ in the photoelectron spectrum, which we call the intermediate energy structure (IES). Using a Coulomb-corrected strong-field approximation, we show it arises from electrons born with large inward velocities that …

[Phys. Rev. Lett. 136, 123203] Published Wed Mar 25, 2026

Optically levitated nanoparticles are promising candidates for the generation of macroscopic quantum states of mechanical motion. Protocols to generate such states expose the particle to a succession of different potentials. Limited reproducibility of the alignment of these potentials across experim…

[Phys. Rev. Lett. 136, 123602] Published Wed Mar 25, 2026

The negatively charged boron vacancy ($V_{\text{B}}^{-}$) in two-dimensional (2D) hexagonal boron nitride (hBN) has emerged as a promising candidate for quantum sensing. The coherence time of $V_{\text{B}}^{-}$ spins which coherent quantum sensing resides in is limited by spin-phonon interactions, while the underlying physical m…

[Phys. Rev. Lett. 136, 123603] Published Wed Mar 25, 2026

Rydberg atom radio frequency sensors are unique in a number of ways, including possessing extraordinary carrier bandwidth, self-calibration, and accuracy. In this Letter, we examine the impact of thermal radiation on Rydberg atom sensors. Antennas are limited by their thermal background, while Rydbe…

[Phys. Rev. Lett. 136, 123201] Published Tue Mar 24, 2026

Spectroscopy of atomic hydrogen produces a new high-precision value for the Rydberg constant and the proton charge radius.

[Phys. Rev. Lett. 136, 123001] Published Mon Mar 23, 2026

We observe and model spin currents arising from chirality and effective spin-exchange interactions in a weakly interacting ${}^6\mathrm{Li}$ Fermi gas. Chirality is introduced by a static displacement between the center of the trapped atoms and the center of an applied magnetic bowl, which produces left- or right…

[Phys. Rev. Lett. 136, 123401] Published Mon Mar 23, 2026

Loss-tolerant detection of squeezed light at 2 µm is accomplished by preamplifying the squeezed quadrature before the detection, mitigating the low detection rate, and increasing observed squeezing from 4 dB to 8 dB.

[Phys. Rev. Lett. 136, 123601] Published Mon Mar 23, 2026

Resonant energy transfer (RET) between the equal parity 1s65s ${}^3{\mathrm{S}}_1$ and 1s66s ${}^3{\mathrm{S}}_1$ Rydberg levels in helium has been observed in low-temperature ($\sim 80\mathrm{mK}$) collisions with ammonia molecules that undergo inversion transitions in their X ${}^1{\mathrm{A}}_1$ ground electronic state. This hybrid Rydberg-atom–polar-molecule…

[Phys. Rev. Lett. 136, 113402] Published Fri Mar 20, 2026

Axionlike particles and similar new pseudoscalar as well as vector bosons coupled to nucleons and electrons are predicted to lead to spin-dependent forces in atoms and ions. We argue that hyperfine structure measurements in hydrogenlike and lithiumlike charge states are a sensitive probe to this eff…

[Phys. Rev. Lett. 136, 113001] Published Thu Mar 19, 2026

Despite growing interest, there is a scarcity of known predictions in the regime where both quantum and general relativistic effects become observable. Here, we investigate a combined atom-field system in a curved spacetime, with a specific focus on gravitational-wave backgrounds. We demonstrate tha…

[Phys. Rev. Lett. 136, 113201] Published Thu Mar 19, 2026

Superradiant burst often arises from photon-mediated interactions within an excited ensemble of emitters, where collective emission leads to a sharp increase in photon intensity. Here, we focus on a nuclear ensemble with cooperative excitations and propose, for the first time, the generation of supe…

[Phys. Rev. Lett. 136, 113601] Published Thu Mar 19, 2026

A continuum analog of the Hatano-Nelson model using a homogeneous spin-orbit-coupled Bose-Einstein condensate shows that repulsive interactions enhance self-acceleration while suppressing the non-Hermitian skin effect.

[Phys. Rev. Lett. 136, 113401] Published Tue Mar 17, 2026

Designing the amplitude and range of couplings in quantum systems is a fundamental tool for exploring a large variety of quantum mechanical effects. Here, we consider off-resonant photon scattering processes on a geometrically shaped molecular cloud. Our analysis shows that such a setup is properly …

[Phys. Rev. Lett. 136, 103403] Published Thu Mar 12, 2026

We investigate the dynamical phase evolution of Coulomb-focused electrons in strong-field ionization. We diffract the electrons with an ultrashort standing light wave to track their time-dependent phase. Our findings show that low-energy electrons exhibit a unique chromosome-shaped diffraction patte…

[Phys. Rev. Lett. 136, 103201] Published Wed Mar 11, 2026

Hydrodynamic attractors characterize hydrodynamiclike evolution in strongly interacting systems, independent of initial conditions or microscopic details, outside the conventional hydrodynamic regime. They explain why hydrodynamic models apply to high-energy nuclear collisions, but so far have only …

[Phys. Rev. Lett. 136, 103402] Published Wed Mar 11, 2026

The infamous weakness of molecular chiroptical responses challenges the all-optical realization of crucial applications such as enantio-selective sorting of chiral molecules, or biasing chiral chemical reactions. Chiral optical cavities are a natural choice for confronting this challenge. Ideally, t…

[Phys. Rev. Lett. 136, 103802] Published Wed Mar 11, 2026

A new ring-shaped resonator for light can do a job that normally requires at least two rings.

[Phys. Rev. Lett. 136, 103803] Published Wed Mar 11, 2026

We demonstrate that secondary ions sputtered from a macrocapillary’s inner surface by the primary beam induce premature saturation of the guiding field, hindering fast ion guiding. By suppressing secondary ion sputtering with grooved surfaces, we achieve a guiding-field potential difference exceedin…

[Phys. Rev. Lett. 136, 103001] Published Mon Mar 09, 2026

We report on the study of itinerant magnetism of lattice-trapped magnetic atoms, driven by magnetic dipole-dipole interactions, in the low-entropy and close-to-unit filling regime. We have used advanced dynamical decoupling techniques to efficiently suppress the sensitivity to magnetic field fluctua…

[Phys. Rev. Lett. 136, 103401] Published Mon Mar 09, 2026

Weyl orbits are topologically protected cyclotron trajectories that connect Weyl nodes of opposite chiralities in momentum space, coupling bulk chiral Landau levels and surface Fermi arcs to produce quantum oscillations under static magnetic fields. While well-studied in condensed matter systems, th…

[Phys. Rev. Lett. 136, 103801] Published Mon Mar 09, 2026

We study the impact of an unshielded dielectric—here, a bare optical fiber—on a ${}^{40}{\mathrm{Ca}}^{+}$ ion held several hundred microns away in a cryogenic surface electrode trap. We observe distance-dependent stray electric fields of up to a few $\mathrm{kV}/\mathrm{m}$ due to the dielectric, which drift on average less than 10% per m…

[Phys. Rev. Lett. 136, 093204] Published Fri Mar 06, 2026

Landau levels (LLs) are the massively degenerate discrete energy spectra of charged particles in a transverse magnetic field, and they lie at the heart of many intriguing phenomena, such as the integer and fractional quantum Hall effects as well as quantized vortices. In this Letter, we consider cou…

[Phys. Rev. Lett. 136, 093602] Published Thu Mar 05, 2026

Strong-field photoelectron holography (SFPH) is a powerful tool for retrieving the phase of photoelectron wave packets, offering insights into the intrinsic atomic/molecular structure and ultrafast dynamics. Here, we generalize the SFPH theory, conventionally applied to plane-phase electron wave pac…

[Phys. Rev. Lett. 136, 093202] Published Wed Mar 04, 2026

We report the observation of a femtosecond strong-laser-field-ionization-induced bimolecular reaction in the acetylene dimer ${({\mathrm{C}}_2{\mathrm{H}}_2)}_2$. Single ionization by the pump laser pulse produces a bound cationic intermediate that undergoes ultrafast intermolecular rearrangement involving hydrogen migration an…

[Phys. Rev. Lett. 136, 093203] Published Wed Mar 04, 2026

We present a density matrix based time dependent projection operator formalism to calculate the beyond mean-field dynamics of systems with non-Markovian local baths and one-to-all interactions. Such models encapsulate the physics of condensed phase systems immersed in optical cavities. We use this m…

[Phys. Rev. Lett. 136, 093601] Published Wed Mar 04, 2026

We report the first direct mapping of the frequency-resolved local density of states (LDOS) in a photonic time crystal (PTC) implemented as an array of time-periodically modulated LC resonators at microwave frequencies. Broadband white noise probes the system and yields an LDOS line shape near the m…

[Phys. Rev. Lett. 136, 093802] Published Tue Mar 03, 2026

Molecular mechanisms that enable collective and upconverted energy transfer from multiple photoacceptors to a nonabsorbing spectator reaction center are highly desirable for efficient light-energy utilization. Here, we show that intermolecular Coulombic decay (ICD), a nonlocal energy-relaxation chan…

[Phys. Rev. Lett. 136, 093201] Published Mon Mar 02, 2026

On-chip narrow linewidth microlasers with real-time wavelength tunability are highly desirable for various applications, including precision metrology, quantum technology, and coherent information processing. Although significant progress has been made by various groups in recent years [M. Li et al…

[Phys. Rev. Lett. 136, 093801] Published Mon Mar 02, 2026

We present a quantum logic scheme mitigating systematic effects in the measurement of magnetic properties of ions caused by temporal magnetic field fluctuations through comagnetometry. This is achieved through simultaneous interrogation of a spectroscopy ion and a cotrapped reference ion with a prec…

[Phys. Rev. Lett. 136, 083203] Published Fri Feb 27, 2026

Pauli crystals are unique geometric structures of noninteracting fermions, resembling crystals, that emerge solely from Fermi statistics and confinement. Unlike genuine quantum crystals that arise from interparticle interactions, Pauli crystals do not break translation symmetry but nonetheless exhib…

[Phys. Rev. Lett. 136, 083405] Published Fri Feb 27, 2026

The Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction and Efimov physics are two distinct quantum phenomena in condensed matter and nuclear physics, respectively. The RKKY interaction describes correlations between impurities mediated by an electron gas, while Efimov physics describes universal bound…

[Phys. Rev. Lett. 136, 083403] Published Thu Feb 26, 2026

We investigate the real-time buildup of short-range correlations in a nondegenerate ultracold Bose gas near a narrow Fano-Feshbach resonance. Using rapid optical control, we quench the closed-channel molecular energy to resonance on submicrosecond timescales and track the evolution of the two-body c…

[Phys. Rev. Lett. 136, 083404] Published Thu Feb 26, 2026

We introduce circular under-threshold RABBITT (cuRABBITT) as a new interferometric method to probe discrete electronic excitations in atoms with attosecond resolution. By combining circularly polarized attosecond pulses with broadband (“rainbow”) spectral analysis, we directly access two-photon ioni…

[Phys. Rev. Lett. 136, 083202] Published Tue Feb 24, 2026

Understanding the dynamics of short-range correlations is a central challenge in strongly interacting Fermi gases. In ultracold gases, these correlations are quantified by the contact parameter, yet measurements to date have been limited to equilibrium systems or relatively slow, global dynamics. He…

[Phys. Rev. Lett. 136, 083402] Published Tue Feb 24, 2026

We present direct experimental evidence of laser-induced charge transfer in the dissociative single ionization of an Ar-Kr dimer: $\mathrm{Ar}\text{−}\mathrm{Kr}+n\hslash \omega \stackrel{\text{ionization}}{⟶}\mathrm{Ar}\text{−}{\mathrm{Kr}}^{+}+e^{-}+m\hslash \omega \stackrel{\text{charge transfer}}{⟶}{\mathrm{Ar}}^{+}\text{−}\mathrm{Kr}+e^{-}\stackrel{\text{dissociation}}{⟶}{\mathrm{Ar}}^{+}+\mathrm{Kr}+e^{-}$. Coincidence detection of ${\mathrm{Ar}}^{+}$ fragments and photoelectrons generated by a 400 nm femtosec…

[Phys. Rev. Lett. 136, 083201] Published Mon Feb 23, 2026

Fluctuations are fundamental in physics and important for understanding and characterizing phase transitions. In this spirit, the phase transition to the Bose-Einstein condensate (BEC) is of specific importance. Whereas fluctuations of the condensate particle number in atomic BECs have been studied …

[Phys. Rev. Lett. 136, 083401] Published Mon Feb 23, 2026

Optical spin textures with nontrivial topology hold promise for structured light and photonic information processing, yet their generation typically relies heavily on externally structured light with care. This raises questions about their universal existence and true robustness. Here, we uncover an…

[Phys. Rev. Lett. 136, 073801] Published Fri Feb 20, 2026

We present a joint experimental and theoretical investigation of nondipole effects in strong-field double ionization of xenon atoms driven by circularly polarized 800 nm laser fields. We observe that the ${\mathrm{Xe}}^{2+}$ ion momentum distribution in the laser polarization plane is Gaussian. The correlated two-e…

[Phys. Rev. Lett. 136, 073201] Published Thu Feb 19, 2026

We report the realization of a blue-detuned magneto-optical trap (BDM) of BaF molecules. The ($1+1$) type BDM and ($1+2$) type conveyor-belt MOT (CB-MOT) are explored. While the ($1+1$) BDM provides only a weak trapping force, the CB-MOT significantly compresses the molecular cloud, achieving a Gaussian r…

[Phys. Rev. Lett. 136, 073402] Published Thu Feb 19, 2026

Moiré physics has transcended spatial dimensions, extending into synthetic domains and enabling novel quantum phenomena. We propose a theoretical model for a two-dimensional (2D) moiré time crystal formed by ultracold atoms, induced by periodic perturbations applied to a nonlattice trap. Our analysi…

[Phys. Rev. Lett. 136, 073401] Published Wed Feb 18, 2026

Rydberg atom triangular arrays in an optical cavity serve as an ideal platform for understanding the interplay between geometric frustration and quantized photons. Using a large-scale quantum Monte Carlo method, we obtain a rich ground state phase diagram. Around half-filling, the infinite long-rang…

[Phys. Rev. Lett. 136, 073602] Published Wed Feb 18, 2026

A novel single-photon source made of a quantum dot embedded in a Dirac cavity provides outstanding performance metrics.

[Phys. Rev. Lett. 136, 073603] Published Wed Feb 18, 2026

Recent experiments demonstrate all-electric spinning of levitated nanodiamonds with embedded nitrogen-vacancy spins. Here, we argue that such gyroscopically stabilized spin rotors offer a promising platform for probing and exploiting quantum spin-rotation coupling of particles hosting a single spin …

[Phys. Rev. Lett. 136, 073604] Published Wed Feb 18, 2026

An optical clock based on a pair of calcium ions achieves a given precision more quickly when the ions are entangled.

[Phys. Rev. Lett. 136, 073601] Published Tue Feb 17, 2026

We demonstrate an all-optically operated centimeter-milligram-scale torsion pendulum for atto-Newton (aN) level force detection, enabled by an ultrathin silica fiber and optical precooling in ultrahigh vacuum. Ten radiation pressure measurement experiments confirm the system’s excellent linearity an…

[Phys. Rev. Lett. 136, 063603] Published Thu Feb 12, 2026

Spin-polarized electron beam sources enable studies of spin-dependent electric and magnetic effects at the nanoscale. We propose a method of creating spin-polarized electrons on an integrated photonics chip by laser-driven nanophotonic fields. A two-stage interaction separated by a free-space drift …

[Phys. Rev. Lett. 136, 063802] Published Thu Feb 12, 2026

X-ray cavity quantum optics with inner-shell transitions has been limited by the spectral overlap between resonant and continuum states. Here, we report the first experimental demonstration of cavity-controlled core-to-core resonant inelastic x-ray scattering (RIXS). We suppress the absorption-edge …

[Phys. Rev. Lett. 136, 063601] Published Wed Feb 11, 2026

Achieving superradiant lasing with an ultranarrow linewidth is crucial for enhancing atomic clock stability in quantum precision measurement. By employing the exceptional point (EP) property of the system, we demonstrate theoretically superradiant lasing with linewidths in the $\mathrm{\mu }\mathrm{Hz}$ range, sustained a…

[Phys. Rev. Lett. 136, 063602] Published Wed Feb 11, 2026

We experimentally investigate the second-order quantum coherence function of a superradiant burst in a cascaded quantum system. We chirally (i.e., direction dependently) couple about 900 cesium atoms to the forward-propagating mode of an optical nanofiber. We then prepare the ensemble close to the m…

[Phys. Rev. Lett. 136, 063402] Published Tue Feb 10, 2026

Soliton mode locking in microresonators enables chip-scale generation of low-noise optical and microwave signals. Pulse pumped solitons offer a platform for broadband microcomb generation with stabilized repetition rates and for exploring soliton physics. In this Letter, we present a theoretical and…

[Phys. Rev. Lett. 136, 063801] Published Tue Feb 10, 2026

Isotope shift metrology in the deep-UV region has been performed for all bosonic isotopes of mercury with a zero nuclear spin, using the technique of frequency-comb referenced, wavelength-modulated, saturated absorption spectroscopy. The absolute center frequencies of the $6{\mathrm{s}}^2{{}^1\mathrm{S}}_0\to 6\mathrm{s}6\mathrm{p}{{}^3\mathrm{P}}_1$ transitio…

[Phys. Rev. Lett. 136, 063001] Published Mon Feb 09, 2026

We demonstrate a method for controlling the outcome of an ultracold chemical few-body reaction by redirecting a tunable fraction of reaction flux from one selected product channel to another one. In the reaction, three ultracold atoms collide to form a diatomic molecule. This product molecule can be…

[Phys. Rev. Lett. 136, 063401] Published Mon Feb 09, 2026

Experiments with structured light beams provide the first observation of “lump” solitions, shape-preserving solitary waves in a two-dimensional setting.

[Phys. Rev. Lett. 136, 053804] Published Fri Feb 06, 2026

Rydberg atoms, with their large transition dipole moments and extreme sensitivity to electric fields, have attracted widespread attention as promising candidates for next-generation quantum precision electrometry. Meanwhile, exceptional points (EPs) in non-Hermitian systems have opened new avenues f…

[Phys. Rev. Lett. 136, 053203] Published Thu Feb 05, 2026

We present a general theoretical framework for helical dichroism (HD), establishing an explicit link between chiral resolution and orbital angular momentum (OAM) exchange in light–matter interaction. Tracing microscopic mechanisms of the OAM transfer, we derive rotational selection rules, which esta…

[Phys. Rev. Lett. 136, 053204] Published Thu Feb 05, 2026

We propose and theoretically characterize three-dimensional spatiotemporal thermalization of a continuous-wave classical light beam propagating along a multimode optical waveguide. By combining a nonequilibrium kinetic approach based on the wave turbulence theory and numerical simulations of the fie…

[Phys. Rev. Lett. 136, 053802] Published Thu Feb 05, 2026

Driven-dissipative optical microcavities provide a versatile platform for exploring lasing dynamics far from equilibrium. While the Kibble-Zurek mechanism provides a framework for understanding non-equilibrium phase transitions, the critical dynamics associated with first-order phase transitions in …

[Phys. Rev. Lett. 136, 053803] Published Thu Feb 05, 2026

Dissociative electron attachment (DEA) to ${\mathrm{HNC}}_3$ is modeled theoretically using a first-principles approach. In ${\mathrm{HNC}}_3+e^{-}$ collisions, there is a low-energy resonance, which has a repulsive character along the $\mathrm{H}+{\mathrm{NC}}_3$ coordinate and becomes a bound electronic state of the $\mathrm{HN}{\mathrm{C}}_3^{-}$ anion near the equilibrium o…

[Phys. Rev. Lett. 136, 053001] Published Wed Feb 04, 2026

Efficient single-photon emitters are desirable for quantum technologies including quantum networks and photonic quantum computers. We investigate the T center, a telecommunications-band emitter in silicon, and find a strong isotope dependence of its excited-state lifetime. In particular, the lifetim…

[Phys. Rev. Lett. 136, 053602] Published Wed Feb 04, 2026

Controlling selective bond cleavage in polyatomic molecules remains a fundamental challenge in photochemistry, primarily due to nonadiabatic dynamics at conical intersections. By combining time-resolved Coulomb explosion imaging with quantum wave packet simulations, we report a striking reversal in …

[Phys. Rev. Lett. 136, 053201] Published Tue Feb 03, 2026