Instability in the Hartmann--Hahn double resonance

Ultra-broadband Heteronuclear Hartmann-Hahn polarization transfer

It is showed on the basis of the multiple-quantum operator algebra space formalism that ultra-broadband heteronuclear Hartmann-Hahn polarization transfer could be achieved by the amplitude- and frequency-modulation quasi-adiabatic excitation (90 degree) pulses, while it is usually difficult for the adiabatic inversion pulses to achieve effectively broadband Hartmann-Hahn transfer in a heteronuclear coupled two-spin system. The adiabatic and quasi-adiabatic pulses have an important property that within their activation bandwidth flip angle of the pulses is independent of the pulse duration and …

Detecting and polarizing nuclear spins with double resonance on a single electron spin

We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. We use Hartmann-Hahn double resonance to coherently enhance the signal from a single nuclear spin while decoupling from the noisy spin-bath, which otherwise limits the detection sensitivity. As a proof-of-principle we: (I) observe coherent oscillations between the NV center and a weakly coupled nuclear spin, (II) demonstrate nuclear bath cooling which prolongs the coherence time of the NV sensor by more than a factor of five. Our results provide a route to na…

利用金刚石中的氮空位（Nitrogen-vacancy, NV）中心解析单分子结构

Resolving single molecule structures with nitrogen-vacancy centers in diamond

本研究提出基于金刚石NV中心的二维核磁共振波谱理论方案，结合强耦合调控与奇异值阈值化矩阵补全算法，可在欠采样下识别谱峰，为单分子结构解析提供新途径。

电偶极自旋共振驱动电子自旋的量子点中的动态核自旋极化

Dynamical nuclear spin polarization in a quantum dot with an electron spin driven by electric dipole spin resonance

本文分析了电驱动单电子自旋诱导的量子点核自旋极化机制，推导了极化率并揭示了其共振特性，为在 GaAs 和 Si 量子点中实现大核极化及稳定 Overhauser 场提供了理论与方法基础。

Optical spin locking of a solid-state qubit

Quantum control of solid-state spin qubits typically involves pulses in the microwave domain, drawing from the well-developed toolbox of magnetic resonance spectroscopy. Driving a solid-state spin by optical means offers a high-speed alternative, which in the presence of limited spin coherence makes it the preferred approach for high-fidelity quantum control. Bringing the full versatility of magnetic spin resonance to the optical domain requires full phase and amplitude control of the optical fields. Here, we imprint a programmable microwave sequence onto a laser field and perform electron spi…