Search for optimum labeling schemes in qubit systems for Quantum Information processing by NMR

Singlet state creation and Universal quantum computation in NMR using Genetic Algorithm

Experimental implementation of a quantum algorithm requires unitary operator decomposition. Here we treat the unitary operator decomposition as an optimization problem and use Genetic Algorithm, a global optimization method inspired by nature's evolutionary process for operator decomposition. As an application, we apply this to NMR Quantum Information Processing and find a probabilistic way of doing universal quantum computation using global hard pulses. We also demonstrate efficient creation of singlet state (as a special case of Bell state) directly from thermal equilibrium using an optimum …

多次测量的量子可观测量标记

Multiple-shot labeling of quantum observables

研究多次数测量下量子可观测量标记问题，证明单次测量无法完美标记时，任何有限次数也无法实现。推导最小错误性能公式并分析其偶奇行为，针对非二元可观测量推导最优单次最小错误成功概率，展示纠缠无助于优化，并提供有限次数标记方案及示例。

Quantum Computation Based on Magic-Angle-Spinning Solid State Nuclear Magnetic Resonance Spectroscopy

Magic-angle spinning (MAS) solid state nuclear magnetic resonance (NMR) spectroscopy is shown to be a promising technique for implementing quantum computing. The theory underlying the principles of quantum computing with nuclear spin systems undergoing MAS is formulated in the framework of formalized quantum Floquet theory. The procedures for realizing state labeling, state transformation and coherence selection in Floquet space are given. It suggests that by this method, the largest number of qubits can easily surpass that achievable with other techniques. Unlike other modalities proposed for…

Realization of logically labeled effective pure states for bulk quantum computation

We report the first use of "logical labeling" to perform a quantum computation with a room-temperature bulk system. This method entails the selection of a subsystem which behaves as if it were at zero temperature - except for a decrease in signal strength - conditioned upon the state of the remaining system. No averaging over differently prepared molecules is required. In order to test this concept, we execute a quantum search algorithm in a subspace of two nuclear spins, labeled by a third spin, using solution nuclear magnetic resonance (NMR), and employing a novel choice of reference frame t…

利用量子增强核磁共振进行单细胞识别

Single-cell identification with quantum-enhanced nuclear magnetic resonance

利用量子增强核磁共振技术，通过检测细胞内质子弛豫时间实现无标记单细胞识别，为稀有细胞分析和个性化医疗提供新方法。

有限尺寸系统中的最优测量型量子热机

Optimal measurement-based quantum thermal machines in a finite-size system

本文提出一种基于测量的量子热机，利用耦合双态量子系统提取工作，推导了三冲程循环的优化准则，并通过数值算法提升性能，展示了测量极限下的效率峰值和对称性破缺对能量间隙的影响。