A5041618773- Quantum Information and Cryptography
- Quantum Mechanics and Applications
- Quantum Computing Algorithms and Architecture
- Mechanical and Optical Resonators
- Diamond and Carbon-based Materials Research
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum optics and atomic interactions
- Spectroscopy and Quantum Chemical Studies
- Force Microscopy Techniques and Applications
- Advanced Fiber Laser Technologies
- Laser-Matter Interactions and Applications
- Quantum many-body systems
- Semiconductor Lasers and Optical Devices
- Atomic and Subatomic Physics Research
- Advanced Thermodynamics and Statistical Mechanics
- Neural Networks and Reservoir Computing
- Advanced Frequency and Time Standards
- Quantum and electron transport phenomena
- Spectroscopy and Laser Applications
- Photonic and Optical Devices
- Advanced Materials Characterization Techniques
- Hate Speech and Cyberbullying Detection
- Nanocomposite Films for Food Packaging
- Probiotics and Fermented Foods
- Biofield Effects and Biophysics
Tsinghua University
2012-2025
National Institute of Standards and Technology
2019-2025
University of Colorado Boulder
2020-2025
Hefei University
2024-2025
National Institute of Standards
2025
University of Colorado System
2025
Qiqihar Medical University
2025
Clover Seed (China)
2025
Dual-type qubits have become a promising way to suppress the crosstalk error of auxiliary operations in large-scale ion trap quantum computation. Here we demonstrate direct entangling gate between dual-type encoded S_{1/2} and D_{5/2} hyperfine manifolds ^{137}Ba^{+} ions. Our scheme is economic hardware, requiring only single 532 nm laser system entangle both qubit types by driving their Raman transitions. We achieve Bell state fidelity 96.3(4)% for Molmer-Sorensen an S-D pair, comparable...
We experimentally realize a universal set of single-bit and two-bit geometric quantum gates by adiabatically controlling solid-state spins in diamond defect. Compared with the nonadiabatic approach, adiabatic scheme for computation offers unique advantage inherent robustness to parameter variations, which is explicitly demonstrated our experiment showing that remain unchanged when driving field amplitude varies factor 2 or detuning fluctuates range comparable inverse gate time. The reported...
Cooling the motion of trapped ions to near quantum ground state is crucial for many applications in information processing and metrology. However, certain motional modes trapped-ion crystals can be difficult cool due weak or zero interaction between cooling radiation, typically laser beams. We overcome this challenge by coupling a mode that interacts weakly with radiation one strongly using parametric modulation trapping potential, thereby enabling indirect interacting mode. In way, we...
We report the first state-independent experimental test of quantum contextuality on a single photonic qutrit (three-dimensional system), based recent theoretical proposal [Yu and Oh, Phys. Rev. Lett. 108, 030402 (2012)]. Our experiment spotlights in its most basic form, way that is independent either state or tensor product structure system.
Abstract The router is a key element for network. We describe scheme to realize genuine quantum routing of single-photon pulses based on cascading conditional gates in Mach-Zehnder interferometer and report proof-of-principle experiment its demonstration using linear optics gates. polarization the control photon routes coherent way path signal while preserving qubit state represented by polarization. demonstrate nature this showing entanglement generated between initially unentangled photons...
Quantum entanglement, the essential resource for quantum information processing, has rich dynamics under different environments. Probing entanglement typically requires exquisite control of complicated system-environment coupling in real experimental systems. Here, by a simple effective solid-state spin bath diamond sample, we observe dynamics, including conventional asymptotic decay as well sudden death, term coined phenomenon complete disappearance after short finite time interval....
Abstract With the recent development of optomechanics, vibration in solids, involving collective motion trillions atoms, gradually enters into realm quantum control. Here, building on remarkable progress optical control motional states diamonds, we report an experimental demonstration teleportation from light beams to vibrational a macroscopic diamond under ambient conditions. Through process tomography, demonstrate average fidelity (90.6±1.0)%, clearly exceeding classical limit 2/3. The...
We present protocols for dissipative entanglement of three trapped-ion qubits and discuss a scheme that uses sympathetic cooling as the dissipation mechanism. This relies on tailored destructive interference to generate any one six entangled W states in three-ion qubit space. Using beryllium-magnesium ion crystal an example system, we theoretically investigate protocol's performance effects likely error sources, including thermal secular motion crystal, calibration imperfections, spontaneous...
We propose and demonstrate a protocol for high-fidelity indirect readout of trapped ion hyperfine qubits, where the state ^{9}Be^{+} qubit is mapped to ^{25}Mg^{+} using laser-driven Raman transitions. By partitioning ground-state manifold into two subspaces representing states choosing appropriate laser parameters, can be made robust spontaneous photon scattering errors on transitions, enabling repetition increased fidelity. combined back-action 1.2_{-0.6}^{+1.1}×10^{-4}...
We demonstrate a simplified method for dissipative generation of an entangled state two trapped-ion qubits. Our implementation produces its target faster and with higher fidelity than previous demonstrations entanglement eliminates the need auxiliary ions. The singlet is generated in ∼7 ms 0.949(4). dominant source infidelity photon scattering. discuss this error strategies mitigation.
The spin-boson model is a prototypical for open quantum dynamics. Here we simulate the using chain of trapped ions in which spin coupled to structured reservoir bosonic modes. We engineer spectral density by adjusting ion number, target location, laser detuning phonon sidebands, and number frequency components laser, observe their effects on collapse revival initially encoded information. Our work demonstrates that trap powerful platform simulating dynamics with complicated structures.
Quantum simulators with hundreds of qubits and engineerable Hamiltonians have the potential to explore quantum many-body models that are intractable for classical computers. However, learning simulated Hamiltonian, a prerequisite any quantitative applications simulator, remains an outstanding challenge due fast increasing time cost qubit number lack high-fidelity universal gate operations in noisy intermediate-scale era. Here, we demonstrate Hamiltonian two-dimensional ion trap simulator 300...
Accurate segmentation of organs or lesions from medical images is essential for accurate disease diagnosis and organ morphometrics. Previously, most researchers mainly added feature extraction modules simply aggregated the semantic features to U-Net network improve accuracy images. However, these improved networks ignore differences different in lack fusion high-level low-level features, which will lead blurred miss boundaries between similar diseased areas. To solve this problem, we propose...
Abstract To construct a quantum network with many end users, it is critical to have cost-efficient way distribute entanglement over different ends. We demonstrate an access network, where the expensive resource, entangled photon source at telecom wavelength and core communication channel, shared by users. Using this we report experimental demonstration of secure multiparty computation protocol, privacy-preserving sum problem, based on cryptography.
Characterization and suppression of noise are essential for the control harmonic oscillators in quantum regime. We measure spectrum a oscillator from low frequency to near resonance by sensing its response amplitude modulated periodic drives with qubit. Using motion trapped ion, we experimentally demonstrate two different implementations combined sensitivity 500 Hz 600 kHz. apply our method intrinsic an ion trap potential previously unaccessed range.
We demonstrate two systems based on vertical-external-cavity surface-emitting lasers (VECSELs) for producing ultraviolet laser light at wavelengths of 235 and 313 nm. The are suitable quantum information processing with trapped beryllium ions. Each system consists a compact, single-frequency, continuous-wave VECSEL high-power near-infrared light, tunable over tens nanometers. One generates 2.4 W 940 nm, using gain mirror GaInAs/GaAs wells, which is converted to 54 mW nm photoionization...
We report the electromagnetically induced transparency (EIT) cooling of ^{137}Ba^{+} ions with a nuclear spin I=3/2, which are good candidate qubits for future large-scale trapped-ion quantum computing. EIT atoms or complex ground-state level structure is challenging due to lack an isolated Λ system, as population can escape from system reduce efficiency. overcome this issue by leveraging pumping laser repopulate subspace, ensuring continuous and effective cooling. cool two radial modes...
We experimentally demonstrate room-temperature storage of quantum entanglement using two nuclear spins weakly coupled to the electronic spin carried by a single nitrogen-vacancy center in diamond. realize universal gate control over three-qubit system and produce entangled states decoherence-free subspace spins. By injecting arbitrary collective noise, we that state has coherence time longer than other an order magnitude our experiment.
Learning the Hamiltonian of a quantum system is indispensable for prediction dynamics and realization high fidelity gates. However, it significant challenge to efficiently characterize which has Hilbert space dimension exponentially growing with size. Here, we develop implement an adaptive method learn effective 11-qubit consisting one electron spin ten nuclear spins associated single nitrogen-vacancy center in diamond. We validate estimated by designing universal gates based on learnt...
Topological defects are discontinuities of a system protected by global properties, with wide applications in mathematics and physics. While previous experimental studies mostly focused on their classical it has been predicted that topological can exhibit quantum superposition. Despite the fundamental interest potential understanding symmetry-breaking dynamics phase transitions, its realization still remains challenge. Here, we report observation superposition trapped-ion simulator. By...