arXiv subjects

Qingze Guan

Publications and source records attributed to Qingze Guan.

15 recordsLinked to original sources

arXiv2026

Open-AoE: An Open Egocentric Manipulation Dataset and Toolchain for Embodied Learning

Egocentric videos of human manipulation provide scalable supervision for embodied intelligence, yet existing resources rarely combine low-cost continuous capture, manipulation-level structured annotations, and reusable tools for robot learning. We present Open-AoE, an open, community-oriented egocentric manipulation dataset and toolchain spanning the full pipeline from smartphone capture to model training. Its first release contains approximately 2,000 hours of manipulation video collected in natural environments by 500+ contributors using 400+ smartphones. The dataset provides text annotations, MANO-based hand poses, camera trajectories, and temporally localized atomic actions. Open-AoE further includes a data processing pipeline that transforms raw recordings into structured samples through temporal action segmentation, semantic annotation, hand reconstruction, and camera trajectory reconstruction. Meanwhile, we provide a separate downstream toolchain supports visualization, cross-embodiment retargeting, model-specific data conversion, and training recipes for VLA policies, WAMs, and World Models. By integrating scalable capture, structured processing, and downstream adaptation, Open-AoE reduces the barriers to both data contribution and reuse, providing practical open infrastructure for embodied model training, human-to-robot transfer, and world modeling.

cs.RO↗

arXiv2026

Few is different: deciphering many-body dynamics in mesoscopic quantum gases

Emergent macroscopic descriptions of matter, such as hydrodynamics, are central to our description of complex physical systems across a wide spectrum of energy scales. The conventional understanding of these many-body phenomena has recently been shaken by a number of experimental findings. Collective behavior of matter has been observed in \emph{mesoscopic} systems, such as high-energy hadron-hadron collisions, or ultra-cold gases with only few strongly interacting fermions. In such systems, the separation of scales between macroscopic and microscopic dynamics (at the heart of any effective theory) is inapplicable. To address the conceptual challenges that arise from these observations and explore the universality of emergent descriptions of matter, the EMMI Rapid Reaction Task Force was assembled. This document summarizes the RRTF discussions on recent theoretical and experimental advances in this rapidly developing field. Leveraging technological breakthroughs in the control of quantum systems, we can now quantitatively explore what it means for a system to exhibit behavior beyond the sum of its individual parts. In particular, the report highlights how the (in)applicability of hydrodynamics and other effective theories can be probed across three principal frontiers: the size frontier, the equilibrium frontier, and the interaction frontier.

cond-mat.quant-gas↗

arXiv2026

Aberration-Free Optical Spectrometer

Optical spectrometers are fundamental to scientific analysis, yet achieving high performance at low cost remains challenging because uncorrected aberrations rapidly degrade spectral resolution and typically necessitate complex, expensive optics. Moreover, to preserve spectral resolution, many compact designs remain fundamentally throughput-limited in terms of having a high f-number and a narrow slit. Here we present SHADES (Stochastic High-throughput Aberration-free Deep-Encoded Spectrometer), a general framework that mitigates the effects of optical aberrations using a stochastic grating array (SGA) coupled with physically grounded deep learning (DL), while substantially increasing optical throughput using encoded multi-slits. We develop a theoretical framework establishing aberration resilient spectroscopy in compact, highly aberrated systems, enabling miniaturization without sacrificing spectral resolution and optical throughput. SHADES utilizes an arbitrary spectrum generator (ASG) for hardware-in-the-loop calibration with a DL-based reconstruction pipeline. We further leverage transfer learning (TL) to reduce calibration data and computation for scalable deployment of SHADES. Experimentally, a micro-SHADES prototype achieves a spectral resolution of 2.4 nm over 450-700 nm and accurately reconstructs fluorescence spectra for chemical identification. Collectively, SHADES provides an aberration-free, high-throughput, low-cost spectrometer architecture suited for compact and scalable sensing applications.

physics.optics↗

arXiv2026

Microscopic Origin of Emergent Elliptic Flow and Molecule Formation in Strongly Interacting Quasi-Two-Dimensional Few-Body Systems

Recent experiments simulating two-dimensional few-fermion systems have observed emergent hydrodynamic behavior, i.e., interaction-driven elliptic flow by adding fermions two at a time [S.~Brandstetter et al., Nat. Phys. (2025)]. Due to the curse of dimensionality and strong correlations, capturing such phenomena beyond two particles remains challenging. Here, we use the ab initio time-dependent explicitly correlated Gaussian (TDECG) method to quantitatively reproduce these experimental observations. With only a moderate number of correlated Gaussian basis functions, our approach obtains converged dynamical observables for systems up to six particles. Furthermore, real-time access to the many-body wavefunction and two-point correlation functions enables us to visualize the transformation from a strongly interacting gas to a stream of paired molecules, i.e., a dynamical BCS-BEC crossover.

cond-mat.quant-gas↗

arXiv2025

Macroscopic Self-Trapping and Dynamical Phase Transition in Momentum Space Bose-Einstein Condensates

Self-trapping is a hallmark phenomenon of nonlinear dynamics. It has significant applications in modern physics, including band structure engineering, phase transition dynamics, quantum metrology, and more. Dilute-gas Bose-Einstein condensates (BECs), in which self-trapping can arise from interatomic interactions, are a prime testbed for probing nonlinear dynamics. In this Letter, we report the observation of self-trapping in a spin-orbit coupled BEC subjected to a stationary optical lattice. We employ Raman-induced spin-orbit coupling, complemented by a matching optical lattice that facilitates coupling between momentum eigenstates of the spin-orbit coupled system. By ramping the Raman detuning, we probe atomic current flow between these eigenstates and identify a clear distinction between a delocalized mixed state and a self-trapped regime. Following a quench of the Raman detuning, the time-averaged atomic current exhibits non-analytic behavior across the transition between these two regimes in certain parameter ranges, signaling a dynamical phase transition in the system.

cond-mat.quant-gas↗

arXiv2024

Rotational magic conditions for ultracold molecules in the presence of Raman and Rayleigh scattering

Molecules have vibrational, rotational, spin-orbit and hyperfine degrees of freedom or quantum states, each of which responds in a unique fashion to external electromagnetic radiation. The control over superpositions of these quantum states is key to coherent manipulation of molecules. For example, the better the coherence time the longer quantum simulations can last. The important quantity for controlling an ultracold molecule with laser light is its complex-valued molecular dynamic polarizability. Its real part determines the tweezer or trapping potential as felt by the molecule, while its imaginary part limits the coherence time. Here, our study shows that efficient trapping of a molecule in its vibrational ground state can be achieved by selecting a laser frequency with a detuning on the order of tens of GHz relative to an electric-dipole-forbidden molecular transition. Close proximity to this nearly forbidden transition allows to create a sufficiently deep trapping potential for multiple rotational states without sacrificing coherence times among these states from Raman and Rayleigh scattering. In fact, we demonstrate that magic trapping conditions for multiple rotational states of the ultracold $^{23}$Na$^{87}$Rb polar molecule can be created.

quant-ph↗

arXiv2023

Engineering Dynamical Phase Diagrams with Driven Lattices in Spinor Gases

We experimentally demonstrate that well-designed driven lattices are versatile tools to simultaneously tune multiple key parameters (namely spin-dependent interactions, spinor phase, and Zeeman energy) for manipulating phase diagrams of spinor gases with negligible heating and atom losses. This opens a new avenue for studying dynamical phase transitions in engineered Hamiltonians. The driven lattice creates additional separatrices in phase space at driving-frequency-determined locations, with progressively narrower separatrices at higher Zeeman energies due to modulation-induced higher harmonics. The vastly expanded range of magnetic fields at which significant spin dynamics occur and improved sensitivities at higher harmonics represent a step towards quantum sensing with ultracold gases.

cond-mat.quant-gas↗

arXiv2023

Manipulation of nonequilibrium spin dynamics of an ultracold gas in a moving optical lattice

The isolation and control of disparate degrees of freedom underpin quantum simulators. We advance the programmability of cold atom quantum simulators with a first realization of the dynamic interplay of spatial and spin degrees of freedom. We experimentally demonstrate that violent spatial evolutions tune long-lived coherent spin dynamics and develop a model of quantum spin-mixing incorporating the spatial evolution via time-dependent spin-spin interactions. Our results open new paths towards the simulation of quantum spin models with tunable interactions via tailored spatial dynamics.

cond-mat.quant-gas↗

arXiv2022

Many-body localization of one-dimensional degenerate Fermi gases with cavity-assisted non-local quasiperiodic interactions

The localization properties of one-dimensional degenerate Fermi gases with cavity-assisted non-local quasiperiodic interactions are numerically studied. Although the cavity-induced interaction is typically nonlocal, it is proved that the eigenstate thermalization hypothesis (ETH) is still applicable in our system depending on the system parameters. We also find the segment of the spectrum corresponding to infinite effective temperature varies for different system parameters, which indicates the spectral range employed in the spectral statistical analysis should be varied accordingly. The features of many-body localization (MBL) are numerically identified by analyzing the spectral statistics and the entanglement entropy using exact diagonalization. These features are further confirmed by our time evolution results. In addition, the number of cavity photons are found stable over long time dynamics in the MBL phase. Such a feature can not only be utilized to nondestructively diagnose the MBL phase by monitoring the number of leaking photons from the cavity, but leveraged for constructing a device to produce a stable number of photons.

cond-mat.quant-gas↗

arXiv2021

Identifying and harnessing dynamical phase transitions for quantum-enhanced sensing

We use the quantum Fisher information (QFI) to diagnose a dynamical phase transition (DPT) in a closed quantum system, which is usually defined in terms of non-analytic behaviour of a time-averaged order parameter. Employing the Lipkin-Meshkov-Glick model as an illustrative example, we find that the DPT correlates with a peak in the QFI that can be explained by a generic connection to an underlying excited-state quantum phase transition that also enables us to also relate the scaling of the QFI with the behaviour of the order parameter. Motivated by the QFI as a quantifier of metrologically useful correlations and entanglement, we also present a robust interferometric protocol that can enable DPTs as a platform for quantum-enhanced sensing.

quant-ph↗

arXiv2021

Single-shot fringe projection profilometry based on Deep Learning and Computer Graphics

Multiple works have applied deep learning to fringe projection profilometry (FPP) in recent years. However, to obtain a large amount of data from actual systems for training is still a tricky problem, and moreover, the network design and optimization still worth exploring. In this paper, we introduce computer graphics to build virtual FPP systems in order to generate the desired datasets conveniently and simply. The way of constructing a virtual FPP system is described in detail firstly, and then some key factors to set the virtual FPP system much close to the reality are analyzed. With the aim of accurately estimating the depth image from only one fringe image, we also design a new loss function to enhance the quality of the overall and detailed information restored. And two representative networks, U-Net and pix2pix, are compared in multiple aspects. The real experiments prove the good accuracy and generalization of the network trained by the data from our virtual systems and the designed loss, implying the potential of our method for applications.

eess.IV↗

arXiv2020

Swirling the weakly bound helium dimer from inside

Controlling the interactions between atoms with external fields opened up new branches in physics ranging from strongly correlated atomic systems to ideal Bose and Fermi gases and Efimov physics. Such control usually prepares samples that are stationary or evolve adiabatically in time. On the other hand, in molecular physics external ultrashort laser fields are employed to create anisotropic potentials that launch ultrafast rotational wave packets and align molecules in free space. Here we combine these two regimes of ultrafast times and low energies. We apply a short laser pulse to the helium dimer, a weakly bound and highly delocalized single bound state quantum system. The laser field locally tunes the interaction between two helium atoms, imparting an angular momentum of $2\hbar$ and evoking an initially confined dissociative wave packet. We record a movie of the density and phase of this wave packet as it evolves from the inside out. At large internuclear distances, where the interaction between the two helium atoms is negligible, the wave packet is essentially free. This work paves the way for future tomography of wave packet dynamics and provides the technique for studying exotic and otherwise hardly accessible quantum systems such as halo and Efimov states.

physics.atm-clus↗

arXiv2020

Nondestructive dispersive imaging of rotationally excited ultracold molecules

A barrier to realizing the potential of molecules for quantum information science applications is a lack of high-fidelity, single-molecule imaging techniques. Here, we present and theoretically analyze a general scheme for dispersive imaging of electronic ground-state molecules. Our technique relies on the intrinsic anisotropy of excited molecular rotational states to generate optical birefringence, which can be detected through polarization rotation of an off-resonant probe laser beam. Using \narb and \rbcs as examples, we construct a formalism for choosing the molecular state to be imaged and the excited electronic states involved in off-resonant coupling. Our proposal establishes the relevant parameters for achieving degree-level polarization rotations for bulk molecular gases, thus enabling high-fidelity nondestructive imaging. We additionally outline requirements for the high-fidelity imaging of individually trapped molecules.

physics.atom-ph↗

arXiv2019

Energetics and structural properties of two- and three-boson systems in the presence of 1D spin-orbit coupling

It was shown recently that the discrete scaling symmetry, which underlies the Efimov effect in the three identical boson system with two-body short-range interactions, survives when single-particle 1D spin-orbit coupling terms are added to the Hamiltonian. Each three-body energy level in the ordinary Efimov scenario turns into an energy manifold that contains four energy levels in the presence of 1D spin-orbit coupling (equal mixture of Rashba-Dresselhaus coupling). This work provides a detailed characterization of the energy levels in these manifolds. The two-boson energies, which enter into the three-boson scattering threshold, are analyzed in detail. Moreover, the structural properties, e.g., momentum distributions of the two- and three-boson systems, are analyzed for various parameter combinations.

cond-mat.quant-gas↗

arXiv2019

Electric-field induced helium-helium resonances

The tunability of the helium-helium interaction through an external electric field is investigated. For a static external field, electric-field induced resonances and associated electric-field induced bound states are calculated for the $^4$He-$^4$He, $^3$He-$^4$He, and $^3$He-$^3$He systems. Qualitative agreement is found with the literature for the $^3$He-$^4$He and $^3$He-$^3$He systems [E. Nielsen, D. V. Fedorov, and A. S. Jensen, Phys. Rev. Lett. {\bf{82}}, 2844 (1999)]. The implications of the predicted electric-field induced resonances for $^4$He-$^4$He on the wave packet dynamics, initiated by intense laser pulses, are investigated. Our results are expected to guide next generation experiments.

cond-mat.quant-gas↗