Chenyong Ju

Single-protein spin resonance spectroscopy under ambient conditions

Single-protein spectroscopy The spin of a single nitrogen-vacancy (NV) center in diamond is a highly sensitive magnetic-field sensor. Shi et al. used the NV center to detect a nitroxidelabeled protein through electron spin resonance under ambient conditions (see the Perspective by Hemmer and Gomes). The strength of the interaction and the details of the hyperfine interaction between the electron and nitrogen spin revealed the position and orientation of the spin label relative to the NV center. The findings also elucidate the dynamical motions of the protein on the diamond surface. Science, this issue p. 1135; see also p. 1072 Electron spin resonance (ESR) signals from a single labeled protein were detected with diamond nitrogen-vacancy centers. [Also see Perspective by Hemmer and Gomes] Magnetic resonance is essential in revealing the structure and dynamics of biomolecules. However, measuring the magnetic resonance spectrum of single biomolecules has remained an elusive goal. We demonstrate the detection of the electron spin resonance signal from a single spin-labeled protein under ambient conditions. As a sensor, we use a single nitrogen vacancy center in bulk diamond in close proximity to the protein. We measure the orientation of the spin label at the protein and detect the impact of protein motion on the spin label dynamics. In addition, we coherently drive the spin at the protein, which is a prerequisite for studies involving polarization of nuclear spins of the protein or detailed structure analysis of the protein itself.

Two-qubit gates between noninteracting qubits in endohedral-fullerene-based quantum computation

We propose a scheme to implement the two-qubit gates between the nuclear spins of the encapsulated atoms in endohedral fullerenes

Quantum games of asymmetric information.

^{15}\mathrm{N}@{\mathrm{C}}_{60}

High-resolution vector microwave magnetometry based on solid-state spins in diamond

or

Experimental realization of quantum algorithm for solving linear systems of equations

^{31}\mathrm{P}@{\mathrm{C}}_{60}

Experimental protection and revival of quantum correlation in open solid systems

, within todays magnetic resonance techniques. Since there is no interaction between the nuclear spins, this scheme employs the electronic spins as medium and two swap operations are proposed to transfer the information between the nuclear spin

Quantum entanglement helps in improving economic efficiency

\frac{1}{2}

Implementation of dynamically corrected gates on a single electron spin in diamond.

and the electronic spin

Demonstration of motion transduction based on parametrically coupled mechanical resonators.

\frac{3}{2}

Quantum discord for investigating quantum correlations without entanglement in solids

, and between two electronic spins