Quantum memory and non-demolition measurement of single phonon state with nitrogen-vacancy centers ensemble

In diamond, the mechanical vibration induced strain can lead to interaction between the mechanical mode and the nitrogen-vecancy (NV) centers. In this work, we propose to utilize the strain induced coupling for the quantum non-demolition (QND) single phonon measurement and memory in diamond. The single phonon in a diamond mechanical resonator can be perfectly absorbed and emitted by the NV centers ensemble (NVE) with adiabatically tuning the microwave driving. An optical laser drives the NVE to the excited states, which have much larger coupling strength to the mechanical mode. By adiabatically eliminating the excited states under large detuning limit, the effective coupling between the mechanical mode and the NVE can be used for QND measurement of the single phonon state. Under realistic experimental conditions, we numerically simulate the scheme. It is found that the fidelity of the absorbing and emitting process can reach a much high value. The overlap between the input and the output phonon shapes can reach $98.57\%$.Comment: 7 pages, 3 figure

New definition of potential spicity by the least square method

Author Posting. © American Geophysical Union, 2018. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 123 (2018): 7351-7365, doi:10.1029/2018JC014306.A differentiable function whose contours are orthogonal to potential density (σ) contours does not exist. However, such a function, called potential spicity (π), can be defined in the least square sense; these two functions form a practically orthogonal coordinate system in potential temperature‐salinity (θ‐S) space. Thus, in addition to the classical potential temperature‐salinity (θ‐S) diagram, seawater properties can be studied in the potential density‐potential spicity (σ − π) diagram.Guangzhou Science and Technology Program key projects. Grant Number: 201804020056 National Natural Science Foundation of China. Grant Numbers: 41476167, 91752108 National Natural Science Foundation of Guangdong Province, China Grant Number: 2016A030311042; Strategic Priority Research Program of the Chinese Academy of Sciences Grant Number: XDA11030302; Guangzhou Science and Technology Program; NSF of Guangdong Province, China2019-04-1

Large Language Models can be Guided to Evade AI-Generated Text Detection

Large Language Models (LLMs) have demonstrated exceptional performance in a variety of tasks, including essay writing and question answering. However, it is crucial to address the potential misuse of these models, which can lead to detrimental outcomes such as plagiarism and spamming. Recently, several detectors have been proposed, including fine-tuned classifiers and various statistical methods. In this study, we reveal that with the aid of carefully crafted prompts, LLMs can effectively evade these detection systems. We propose a novel Substitution-based In-Context example Optimization method (SICO) to automatically generate such prompts. On three real-world tasks where LLMs can be misused, SICO successfully enables ChatGPT to evade six existing detectors, causing a significant 0.54 AUC drop on average. Surprisingly, in most cases these detectors perform even worse than random classifiers. These results firmly reveal the vulnerability of existing detectors. Finally, the strong performance of SICO suggests itself as a reliable evaluation protocol for any new detector in this field

Text Mining-Based Patent Analysis for Automated Rule Checking in AEC

Automated rule checking (ARC), which is expected to promote the efficiency of the compliance checking process in the architecture, engineering, and construction (AEC) industry, is gaining increasing attention. Throwing light on the ARC application hotspots and forecasting its trends are useful to the related research and drive innovations. Therefore, this study takes the patents from the database of the Derwent Innovations Index database (DII) and China national knowledge infrastructure (CNKI) as data sources and then carried out a three-step analysis including (1) quantitative characteristics (i.e., annual distribution analysis) of patents, (2) identification of ARC topics using a latent Dirichlet allocation (LDA) and, (3) SNA-based co-occurrence analysis of ARC topics. The results show that the research hotspots and trends of Chinese and English patents are different. The contributions of this study have three aspects: (1) an approach to a comprehensive analysis of patents by integrating multiple text mining methods (i.e., SNA and LDA) is introduced ; (2) the application hotspots and development trends of ARC are reviewed based on patent analysis; and (3) a signpost for technological development and innovation of ARC is provided

Research on the influence of power frequency electric field of pantograph on passengers’ health in high-speed EMU

In this work we discussed the safety of the electric field environment in the No.3 carriage where the pantograph is located. DSA380 pantograph, CRH5 EMU carriage and passengers’ models were established to study the electric field exposure of passengers at different positions. The results showed that Emax in the carriage without passengers is 1.173 x 10 6 mV/m. Then we set the passengers’ positions according to the electric field distribution in the carriage without passengers and obtained that Emax in the carriage with passengers is 3.195 x 10 6 mV/m. It can be seen that the maximum induced electric field intensity of passengers at different positions appears on the soles of shoes, the maximum value is 3.028 x 105 mV/m, the maximum induced current density occurs at the ankle, its maximum value is 3.476 x 10 -5 A/m 2. It can be concluded that the maximum induced electric field intensity of passenger’s head appears in the cerebrospinal fluid area, with a maximum value of 202.817 mV/m, and the maximum induced electric field intensity of passenger’s head at the door is larger than that in the middle of the carriage. The maximum values of the induced electric field intensity in all tissues of passengers are much smaller than the basic limits of electromagnetic exposure to the public set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). This study indicated that the pantograph has little influence on the electric field environment in the carriage under working state, and will not cause any health hazard to the passengers in this working frequency electric field environment

The linear and nonlinear Jaynes-Cummings model for the multiphoton transition

With the Jaynes-Cummings model, we have studied the atom and light field quantum entanglement of multiphoton transition, and researched the effect of initial state superposition coefficient $C_{1}$, the transition photon number $N$, the quantum discord $\delta$ and the nonlinear coefficient $\chi$ on the quantum entanglement degrees. We have given the quantum entanglement degrees curves with time evolution, and obtained some results, which should have been used in quantum computing and quantum information.Comment: arXiv admin note: text overlap with arXiv:1404.0821, arXiv:1205.0979 by other author