Towards new understanding of nuclear rotation

Nuclear Surface Acoustic Resonance with Spin-Rotation Coupling

We show that, under an appropriate out-of-plane static magnetic field, nuclear spins in a thin specimen on a surface acoustic wave (SAW) cavity can be resonantly excited and detected through spin-rotation coupling. Since such a SAW cavity can have the quality factor as high as $10^{4}$ and the mode volume as small as $10^{-2}$ mm$^{3}$ the signal-to-noise ratio in detecting the resonance is estimated to be quite high. We argue that detecting nuclear spin resonance of a single flake of an atomically-thin layer of two-dimensional semiconductor, which has so far been beyond hope with the conventi…

Quantum control of nuclear spin qubits in a rapidly rotating diamond

Nuclear spins in certain solids couple weakly to their environment, making them attractive candidates for quantum information processing and inertial sensing. When coupled to the spin of an optically-active electron, nuclear spins can be rapidly polarized, controlled and read via lasers and radiofrequency fields. Possessing coherence times of several milliseconds at room temperature, nuclear spins hosted by a nitrogen-vacancy center in diamond are thus intriguing systems to observe how classical physical rotation at quantum timescales affects a quantum system. Unlocking this potential is hampe…

Nuclear Spin Gyroscope based on the Nitrogen Vacancy Center in Diamond

A rotation sensor is one of the key elements of inertial navigation systems and compliments most cellphone sensor sets used for various applications. Currently, inexpensive and efficient solutions are mechanoelectronic devices, which nevertheless lack long-term stability. Realization of rotation sensors based on spins of fundamental particles may become a drift-free alternative to such devices. Here, we carry out a proof-of-concept experiment, demonstrating rotation measurements on a rotating setup utilizing nuclear spins of an ensemble of NV centers as a sensing element with no stationary ref…

Logical operations with single x-ray photons via dynamically-controlled nuclear resonances

The implementation of logical operations on polarization-encoded x-rays via resonant light-nucleus interactions is theoretically investigated. We show that by means of resonant scattering off nuclei and fast rotations of the nuclear hyperfine magnetic field to control the polarization of the output photon, single-qubit logical gates can be simulated. A second control qubit may be employed to trigger the magnetic field rotation, thus allowing several implementation choices for a controlled NOT gate for x-ray photons.

Robust optical readout and characterization of nuclear spin transitions in nitrogen-vacancy ensembles in diamond

Nuclear spin ensembles in diamond are promising candidates for quantum sensing applications, including rotation sensing. Here we perform a characterization of the optically detected nuclear-spin transitions associated with the 14N nuclear spin within diamond nitrogen vacancy (NV) centers. We observe nuclear-spin-dependent fluorescence with the contrast of optically detected 14N nuclear Rabi oscillations comparable to that of the NV electron spin. Using Ramsey spectroscopy, we investigate the temperature and magnetic-field dependence of the nuclear spin transitions in the 77.5-420 K and 350-675…

基于三维旋转诱导 Berry 相位的超高灵敏度磁传感器

Ultra-sensitive magnetic sensor based on 3-dimensional rotation induced Berry phase

提出基于三维旋转诱导Berry相位测量直流磁场的新方法，理论证明14N核自旋静态磁场灵敏度可达10^(-7) T/Hz^(1/2)/N^(1/2)。

Exact quantum dynamics developments for floppy molecular systems and complexes

Molecular rotation, vibration, internal rotation, isomerization, tunneling, intermolecular dynamics of weakly and strongly interacting systems, intra-to-inter-molecular energy transfer, hindered rotation and hindered translation over surfaces are important types of molecular motions. Their fundamentally correct and detailed description can be obtained by solving the nuclear Schrödinger equation on a potential energy surface. Many of the chemically interesting processes involve quantum nuclear motions which are `delocalized' over multiple potential energy wells. These `large-amplitude' motions …

Quantum bath control with nuclear spin state selectivity via pulse-adjusted dynamical decoupling

Dynamical decoupling (DD) is a powerful method for controlling arbitrary open quantum systems. In quantum spin control, DD generally involves a sequence of timed spin flips ($π$ rotations) arranged to average out or selectively enhance coupling to the environment. Experimentally, errors in the spin flips are inevitably introduced, motivating efforts to optimise error-robust DD. Here we invert this paradigm: by introducing particular control "errors" in standard DD, namely a small constant deviation from perfect $π$ rotations (pulse adjustments), we show we obtain protocols that retain the adva…

基于金刚石中 $^{15}$NV 中心的仿真核自旋陀螺仪

Emulated nuclear spin gyroscope with $^{15}$NV centers in diamond

针对 NV 陀螺仪大型自旋系综相干性退化问题，研究利用 $^{15}$NV 中心核自旋，揭示相干衰减机制并开发仅控制电子自旋的鲁棒相干保护协议，实现退相干时间提升 15 倍及陀螺仪灵敏度提升一个数量级。

金刚石核自旋陀螺仪的演示

Demonstration of diamond nuclear spin gyroscope

本研究演示了基于金刚石NV色心本征$^{14}$N核自旋的旋转传感器，采用光学极化读出与射频双量子脉冲协议，抑制温度敏感度且无需NV电子自旋共振微波脉冲，实现了4.7°/√s的灵敏度与0.4°/s的偏置稳定性。

Nuclear Spins in Nanostructures

We review recent theoretical and experimental advances toward understanding the effects of nuclear spins in confined nanostructures. These systems, which include quantum dots, defect centers, and molecular magnets, are particularly interesting for their importance in quantum information processing devices, which aim to coherently manipulate single electron spins with high precision. On one hand, interactions between confined electron spins and a nuclear-spin environment provide a decoherence source for the electron, and on the other, a strong effective magnetic field that can be used to execut…

三原子分子中振动、转动和电子波包动力学的同时成像

Simultaneous imaging of vibrational, rotational, and electronic wave packet dynamics in a triatomic molecule

本研究针对强耦合下分子多自由度动力学表征难题，结合时间分辨CEI与量子模拟，同时观测了二氧化硫的振动、转动及电子波包演化，验证了多重符合CEI用于多原子分子耦合运动研究的有效性。