The issue of information security is closely related to every aspect of daily life. For pursuing a higher level of security, much effort has been continuously invested in the development of information security technologies based on encryption and storage. Current approaches using single-dimension information can be easily cracked and imitated due to the lack of sufficient security. Multidimensional information encryption and storage are an effective way to increase the security level and can protect it from counterfeiting and illegal decryption. Since light has rich dimensions (wavelength, duration, phase, polarization, depth, and power) and synergy between different dimensions, light as the input is one of the promising candidates for improving the level of information security. In this review, based on six different dimensional features of the input light, we mainly summarize the implementation methods of multidimensional information encryption and storage including material preparation and response mechanisms. In addition, the challenges and future prospects of these information security systems are discussed.

Senyang Liu

Xiaohu Liu

Jinying Yuan

Jie Bao

Multidimensional Information Encryption and Storage: When the Input Is Light

Recent progress has been made on the synthesis and characterization of metal halide perovskite magic-sized clusters (PMSCs) with ABX3 composition (<svg xmlns="http://www.w3.org/2000/svg" id="M1" style="vertical-align:-3.266399pt" height="13.3157pt" version="1.1" viewBox="-0.0498162 -10.0493 75.7774 13.3157" width="75.7774pt">


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</svg>, Br-, or I-). However, their mechanism of growth and structure is still not well understood. In our effort to understand their structure and growth, we discovered that a new species can be formed without the CH3NH3+ component, which we name as molecular clusters (MCs). Specifically, CH3NH3PbBr3 PMSCs, with a characteristic absorption peak at 424 nm, are synthesized using PbBr2 and CH3NH3Br as precursors and butylamine (BTYA) and valeric acid (VA) as ligands, while MCs, with an absorption peak at 402 nm, are synthesized using solely PbBr2 and BTYA, without CH3NH3Br. Interestingly, PMSCs are converted spontaneously overtime into MCs. An isosbestic point in their electronic absorption spectra indicates a direct interplay between the PMSCs and MCs. Therefore, we suggest that the MCs are precursors to the PMSCs. From spectroscopic and extended X-ray absorption fine structure (EXAFS) results, we propose some tentative structural models for the MCs. The discovery of the MCs is critical to understanding the growth of PMSCs as well as larger perovskite quantum dots (PQDs) or nanocrystals (PNCs).

Evan T. Vickers

Ziyi Chen

Vivien Cherrette

Tyler Smart

Peng Zhang

Yuan Ping

Jin Z. Zhang

Interplay between Perovskite Magic-Sized Clusters and Amino Lead Halide Molecular Clusters

We explore a potential LISA-Taiji network to fast and accurately localize the coalescing massive black hole binaries. For an equal-mass binary located at redshift of 1 with a total intrinsic mass of <svg xmlns="http://www.w3.org/2000/svg" id="M1" style="vertical-align:-3.8191pt" height="14.3352pt" version="1.1" viewBox="-0.0498162 -10.5161 35.2658 14.3352" width="35.2658pt">


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</svg>, the LISA-Taiji network may achieve almost four orders of magnitude improvement on the source localization region compared to an individual detector. The precision measurement of sky location from the gravitational-wave signal may completely identify the host galaxy with low redshifts prior to the final black hole merger. Such identification of the host galaxy is vital for the follow-up variability in electromagnetic emissions of the circumbinary disc when the binary merges to a new black hole and enables the coalescing massive black hole binaries to be used as a standard siren to probe the expansion history of the Universe.

Wen-Hong Ruan

Chang Liu

Zong-Kuan Guo

Yue-Liang Wu

Rong-Gen Cai

The LISA-Taiji Network: Precision Localization of Coalescing Massive Black Hole Binaries

Emotion recognition has been used widely in various applications such as mental health monitoring and emotional management. Usually, emotion recognition is regarded as a text classification task. Emotion recognition is a more complex problem, and the relations of emotions expressed in a text are nonnegligible. In this paper, a hierarchical model with label embedding is proposed for contextual emotion recognition. Especially, a hierarchical model is utilized to learn the emotional representation of a given sentence based on its contextual information. To give emotion correlation-based recognition, a label embedding matrix is trained by joint learning, which contributes to the final prediction. Comparison experiments are conducted on Chinese emotional corpus RenCECps, and the experimental results indicate that our approach has a satisfying performance in textual emotion recognition task.

Jiawen Deng

Fuji Ren

Hierarchical Network with Label Embedding for Contextual Emotion Recognition

Acoustic tweezers have great application prospects because they allow noncontact and noninvasive manipulation of microparticles in a wide range of media. However, the nontransparency and heterogeneity of media in practical applications complicate particle trapping and manipulation. In this study, we designed a 1.04&#x2009;MHz 256-element 2D matrix array for 3D acoustic tweezers to guide and monitor the entire process using real-time 3D ultrasonic images, thereby enabling acoustic manipulation in nontransparent media. Furthermore, we successfully performed dynamic 3D manipulations on multiple microparticles using multifoci and vortex traps. We achieved 3D particle manipulation in heterogeneous media (through resin baffle and ex vivo macaque and human skulls) by introducing a method based on the time reversal principle to correct the phase and amplitude distortions of the acoustic waves. Our results suggest cutting-edge applications of acoustic tweezers such as acoustical drug delivery, controlled micromachine transfer, and precise treatment.

Ye Yang

Teng Ma

Sinan Li

Qi Zhang

Jiqing Huang

Yifei Liu

Jianwei Zhuang

Yongchuan Li

Xuemin Du

Lili Niu

Yang Xiao

Congzhi Wang

Feiyan Cai

Hairong Zheng

Self-Navigated 3D Acoustic Tweezers in Complex Media Based on Time Reversal

About this journal

The open access journal Research, published in association with CAST, publishes innovative, wide-ranging research in life sciences, physical sciences, engineering and applied science.

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Meet the editorial board

Research's&nbsp;Editorial Board includes international experts in fields ranging from life sciences to physical sciences. Tianhong Cui of University of Minnesota and Wei Huang of Northwestern Polytechnical University, China serve as the Editors-in-Chief of the journal.

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•&nbsp;<a href="/research-special-issues/metamaterial">Metamaterial</a>

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