Article
Optics
Olga Korotkova, Yalcin Ata
Summary: This study reveals the evolution of a 4 x 4 matrix composed of scintillation indices of single-point Stokes parameters of a stationary electromagnetic beam-like optical field in classic, weak atmospheric turbulence. Depending on the source parameters chosen, the relationship between the matrix elements of the propagating beam and those produced by turbulence can be range-separated or conjoined. The results, analyzed using the unified theory of coherence and polarization with the extended Huygens-Fresnel integral approach, may be important for building robust communication and sensing systems in the presence of atmospheric fluctuations.
Article
Optics
Naru Yoneda, Xiangyu Quan, Osamu Matoba
Summary: In this study, a method is proposed to see through a random light field in real-time using a polarization camera in single-shot generalized Hanbury Brown-Twiss experiments. The target intensity distribution is obtained from a complex coherence function calculated from auto-correlation and cross-correlation functions of phase-shifted speckle intensity distributions. The phase-shifted speckle intensity distributions are simultaneously obtained through parallel phase-shifting digital holography. Experimental results demonstrate that the proposed method can image a moving object in a random light field using a measured complex coherence function through the van Cittert-Zernike theorem.
Article
Optics
Zong-Da Zhang, Si-Yu Yin, Li-Cheng Wang, Ying-De Wang, Yun-Fei Li, Zhen-Nan Tian, Qi-Dai Chen
Summary: An array of single NV centers was prepared using the femtosecond laser direct writing method to address the accuracy and consistency issues in static magnetic field detection. The prepared NV centers have fewer defects and good stress uniformity, with an average spatial positioning error of only 0.2 μm. This array enables high accuracy measurement of magnetic field vector and gradient.
Article
Chemistry, Physical
Chengyuan Yang, Zhaohong Mi, Huining Jin, Thirumalai Venkatesan, Ratnakar Vispute, Andrew A. Bettiol
Summary: We report a method for large-scale fabrication of negatively charged Silicon-vacancy (SiV-) centers in diamond membranes using MeV Helium ion implantation. Despite the polycrystalline structure of the diamond membranes, the SiV- centers exhibit a fluorescence lifetime comparable to those fabricated in single crystal diamonds. Patterning of SiV- centers with varying densities is demonstrated using a focused ion beam.
Article
Chemistry, Multidisciplinary
Alexander Wood, Artur Lozovoi, Zi-Huai Zhang, Sachin Sharma, Gabriel I. Lopez-Morales, Harishankar Jayakumar, Nathalie P. de Leon, Carlos A. Meriles
Summary: Using confocal fluorescence microscopy, we observe the charge interconversion process between all three charge states of the silicon vacancy (SiV) center in diamond at room temperature. We uncover the two-step capture process of diffusing, photogenerated holes that leads to the formation of SiV0, and demonstrate the reverse process induced by continuous red illumination. These findings provide insight into the charge dynamics of SiV and hold promise for nanoscale sensing and quantum information processing.
Article
Chemistry, Physical
Mariusz Mrozek, Mateusz Schabikowski, Marzena Mitura-Nowak, Janusz Lekki, Marta Marszalek, Adam M. Wojciechowski, Wojciech Gawlik
Summary: The experimental study focused on the longitudinal and transverse relaxation of negatively charged nitrogen-vacancy centers in diamond monocrystals prepared by 1.8 MeV proton implantation. Results showed that proton implantation technique can be versatile in controlling the production of nitrogen-vacancy color centers in thin films.
Article
Chemistry, Multidisciplinary
Changhao Li, Rouhollah Soleyman, Mohammad Kohandel, Paola Cappellaro
Summary: A molecular transducer based on NV centers has been proposed to convert SARS-CoV-2 RNA into magnetic noise signal for optical readout. This sensor demonstrates high sensitivity, low false negative rate, and fast detection of the virus.
Article
Materials Science, Multidisciplinary
Lukas Razinkovas, Marek Maciaszek, Friedemann Reinhard, Marcus W. Doherty, Audrius Alkauskas
Summary: The study conducted ab initio calculations on the photoionization characteristics of the NV center in diamond, revealing the mechanism of spin polarization induced electron state transition. These findings are crucial for interpreting and designing experiments on photoionization of NV centers.
Article
Optics
Li Chen, Ziyang Chen, Rakesh Kumar Singh, R. V. Vinu, Jixiong Pu
Summary: Quantitative phase imaging (QPI) is essential for exploring properties of transparent and absorption-free samples, with holography widely used to record both amplitude and phase of optical fields. However, conventional holographic methods face challenges when objects are obscured by scattering media. Advanced holographic methods based on Hanbury Brown-Twiss (HBT) approach, such as off-axis holography, phase-shifting holography, and polarization-based phase-shifting holography, show enhanced imaging capabilities and wider field of view in comparison. The use of orthogonally-polarized light as reference light in the third method demonstrates superior performance in imaging complex phase samples.
OPTICS AND LASERS IN ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Frantisek Trojanek, Karol Hamracek, Martin Hanak, Marian Varga, Alexander Kromka, Oleg Babcenko, Lukas Ondic, Petr Maly
Summary: Diamond thin films with a high-density of light-emitting negatively charged silicon vacancy (SiV) centers can be prepared at a relatively low cost, which has potential applications in photonics or sensing. The composition of the films, which consist of diamond grains with SiV centers and sp(2)-carbon phase, can be adjusted by changing the preparation conditions. Surface defects and the sp(2)-related defects in the grains can trap the carriers excited within the SiV centers, leading to a decrease in their internal photoluminescence (PL) quantum efficiency.
Article
Physics, Applied
Kelsey M. Bates, Matthew W. Day, Christopher L. Smallwood, Rachel C. Owen, Tim Schroder, Edward Bielejec, Ronald Ulbricht, Steven T. Cundiff
Summary: An ensemble of silicon vacancy (SiV-) centers in diamond was probed using two-pulse correlation spectroscopy and multidimensional coherent spectroscopy. Two main distinct families of SiV- centers were identified, and local strain tensor was calculated based on measured spectra. Variations in strain tensor were observed at multiple points on the sample surface.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Nattakarn Suntornwipat, Saman Majdi, Markus Gabrysch, Kiran Kumar Kovi, Viktor Djurberg, Ian Friel, Daniel J. Twitchen, Jan Isberg
Summary: Researchers demonstrate electrostatic control of valley currents in ultrapure single-crystalline diamond, proposing a model to interpret experimental data and paving the way for the development of valleytronic devices.
Article
Physics, Applied
Shahriar Aghaeimeibodi, Daniel Riedel, Alison E. Rugar, Constantin Dory, Jelena Vuckovic
Summary: The study investigates the electrical tuning of Sn-V- centers in diamond through the direct-current Stark effect, demonstrating a tuning range beyond 1.7 GHz with both quadratic and linear dependence on the applied electric field. The researchers confirm that the observed tuning effect is a result of the applied electric field, distinct from thermal tuning due to Joule heating, suggesting Stark tuning as a promising avenue to overcome detunings between emitters and enabling the realization of multiple identical quantum nodes.
PHYSICAL REVIEW APPLIED
(2021)
Article
Education, Scientific Disciplines
Arnt Inge Vistnes, Joakim Bergli
Summary: Hanbury Brown and Twiss determined the angular size of a star and a waterfall by studying the cross-correlation in intensity fluctuation recorded by detectors, showing that this principle works for different types of waves, and ultimately providing a bridge to the original HBT work.
AMERICAN JOURNAL OF PHYSICS
(2022)
Article
Optics
Muhib Omar, Andreas Conta, Andreas Westerhoff, Raphael Hasse, Georgios Chatzidrosos, Dmitry Budker, Arne Wickenbrock
Summary: We propose a design to enhance the collected fluorescence of nitrogen-vacancy color centers in diamond for quantum-sensing. Our experimental results demonstrate a 3.8-fold increase in collected fluorescence when comparing opposite emitting surfaces, which is consistent with ray-tracing simulation. This design improves the sensitivity in optical readout-based measurements of various physical quantities.
Review
Physics, Multidisciplinary
Kishor Bharti, Alba Cervera-Lierta, Thi Ha Kyaw, Tobias Haug, Sumner Alperin-Lea, Abhinav Anand, Matthias Degroote, Hermanni Heimonen, Jakob S. Kottmann, Tim Menke, Wai-Keong Mok, Sukin Sim, Leong-Chuan Kwek, Alan Aspuru-Guzik
Summary: NISQ computers, composed of noisy qubits, are already being used in various fields. This review provides a comprehensive summary of NISQ computational paradigms and algorithms and introduces various benchmarking and software tools for programming and testing NISQ devices.
REVIEWS OF MODERN PHYSICS
(2022)
Article
Quantum Science & Technology
Kian Hwee Lim, Tobias Haug, Leong Chuan Kwek, Kishor Bharti
Summary: Simulating quantum dynamics is easier on quantum computers than on classical computers, but current quantum devices lack the capability for fault-tolerant quantum algorithms. Hybrid classical quantum algorithms, such as variational quantum algorithms, have been proposed to effectively use current quantum devices. The diagonalisation based approach is a promising method for quantum simulation in the NISQ era, but it requires a feedback loop between classical and quantum computers. The classical quantum fast forwarding (CQFF) algorithm is a new diagonalisation based algorithm that removes the need for classical-quantum feedback loop and controlled multi-qubit unitaries. It offers high accuracy and the ability to systematically increase accuracy, and it is easy to implement in the NISQ era.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Wayne J. Chetcuti, Tobias Haug, Leong-Chuan Kwek, Luigi Amico
Summary: We study the persistent current in a system of SU(N) fermions with repulsive interaction. We find surprising effects, where spinons can be created and change the nature of the elementary flux quantum due to spin correlations, (effective) magnetic flux, and interaction. These changes have a dramatic impact on the persistent current and can detect quantum phase transitions.
Article
Chemistry, Physical
Chee-Kong Lee, Jonathan Wei Zhong Lau, Liang Shi, Leong Chuan Kwek
Summary: Quantum computers have the potential to simulate chemical systems beyond classical computers. Recent advances in hybrid quantum-classical approaches have enabled the determination of ground or low energy states of molecular systems. This study extends quantum simulations of chemistry to time-dependent processes by simulating energy transfer in organic semiconducting molecules.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Multidisciplinary Sciences
H. H. Zhu, J. Zou, H. Zhang, Y. Z. Shi, S. B. Luo, N. Wang, H. Cai, L. X. Wan, B. Wang, X. D. Jiang, J. Thompson, X. S. Luo, X. H. Zhou, L. M. Xiao, W. Huang, L. Patrick, M. Gu, L. C. Kwek, A. Q. Liu
Summary: Large-scale, highly integrated, and low-power-consuming hardware is crucial for optical neural networks to achieve advanced optical computing. Traditional experimental implementations have limited scalability and consume excessive power. This study proposes an integrated diffractive optical network (IDNN) that utilizes two ultracompact diffractive cells and a small number of MZIs to perform parallel Fourier transforms, convolution operations, and application-specific optical computing. The footprint and energy consumption of the IDNN scale linearly with the input data dimension, resulting in significant reductions compared to traditional MZI-based ONNs. Experimental results on MNIST and Fashion-MNIST datasets demonstrate a similar level of accuracy and approximately 10-fold reduction in footprint and energy consumption. The IDNN chip shows promising potential for scalable and low-power-consumption optical computational chips for optical artificial intelligence.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Jonathan W. Z. Lau, Tobias Haug, Leong C. Kwek, Kishor Bharti
Summary: This work proposes a new algorithm, truncated Taylor quantum simulator (TQS), that provides a conceptual unification between NISQ algorithms for the Hamiltonian ground state problem and Hamiltonian simulation. The algorithm has multiple advantages and bypasses the barren plateau problem by construction. The study also provides a systematic approach to improve the accuracy of the algorithm.
Article
Quantum Science & Technology
Yuan Li, Lingxiao Wan, Hui Zhang, Huihui Zhu, Yuzhi Shi, Lip Ket Chin, Xiaoqi Zhou, Leong Chuan Kwek, Ai Qun Liu
Summary: This study presents a scheme for implementing three-qubit Fredkin and Toffoli gates on a programmable quantum photonic chip, which is experimentally demonstrated. The scheme can also be used to realize other two-qubit quantum gates, providing a new approach for advanced quantum chip processors.
NPJ QUANTUM INFORMATION
(2022)
Article
Multidisciplinary Sciences
Hui Zhang, Lingxiao Wan, Tobias Haug, Wai-Keong Mok, Stefano Paesani, Yuzhi Shi, Hong Cai, Lip Ket Chin, Muhammad Faeyz Karim, Limin Xiao, Xianshu Luo, Feng Gao, Bin Dong, Syed Assad, M. S. Kim, Anthony Laing, Leong Chuan Kwek, Ai Qun Liu
Summary: This paper proposes an approach to reduce the resource costs for quantum teleportation of subspaces in high-dimensional systems using quantum autoencoders and demonstrates it experimentally on an integrated photonic platform. By training the on-chip autoencoder with unsupervised machine learning, compression and teleportation of any state from a high-dimensional subspace are achieved.
Article
Physics, Multidisciplinary
Andreas Burger, Leong Chuan Kwek, Dario Poletti
Summary: This study investigates how to simulate open quantum dynamics in a digital quantum computer, showing that simulating the unitary portion of the dynamics is key while the dissipative part can lead to a more noise-resistant simulation.
Article
Optics
Hui Zhang, Jonathan Wei Zhong Lau, Lingxiao Wan, Liang Shi, Yuzhi Shi, Hong Cai, Xianshu Luo, Guo-Qiang Lo, Chee-Kong Lee, Leong Chuan Kwek, Ai Qun Liu
Summary: This study demonstrates the capability of photonic neural networks in predicting the quantum mechanical properties of molecules and shows that multiple properties can be learned simultaneously in a photonic chip through a multi-task regression learning algorithm. It is the first application of photonics technology in machine learning for computational chemistry and molecular sciences, such as drug discovery and materials design, which is of great significance.
LASER & PHOTONICS REVIEWS
(2023)
Review
Physics, Multidisciplinary
Luigi Amico, Dana Anderson, Malcolm Boshier, Jean -Philippe Brantut, Leong-Chuan Kwek, Anna Minguzzi, Wolf von Klitzing
Summary: This article reviews the recent progress in atomtronics and atomtronics-based quantum technology, including the basic principles, experimental techniques, and physics involved. The main experimental observations, outstanding questions, and potential applications in various quantum technologies are discussed.
REVIEWS OF MODERN PHYSICS
(2022)
Article
Physics, Multidisciplinary
Yuan Shen, Hong Yi Soh, Leong-Chuan Kwek, Weijun Fan
Summary: This paper proposes using classical and quantum Fisher information as alternative metrics to detect and measure quantum synchronization. The connection between Fisher information and quantum synchronization is established, showing that both classical and quantum Fisher information can be used as more general indicators of quantum phase synchronization. Advantages in Fisher information-based measures, especially in 2-to-1 synchronization, are demonstrated. Furthermore, the impact of noise on synchronization measures is analyzed, revealing the robustness and susceptibility of each method in the presence of dissipation and decoherence.
Article
Optics
Yuan Shen, Wai-Keong Mok, Changsuk Noh, Ai Qun Liu, Leong-Chuan Kwek, Weijun Fan, Andy Chia
Summary: This article proposes a new approach to quantum synchronization by using an approximate model of the Duffing-van der Pol oscillator. It captures interesting phenomena in the deep-quantum strongly nonlinear regime, such as amplitude death on resonance and nonlinearity-induced position correlations.
Article
Materials Science, Multidisciplinary
Kelvin Koor, Raditya Weda Bomantara, Leong Chuan Kwek
Summary: This work investigates the interplay between periodic driving, interaction effects, and Z2 symmetry in a two-dimensional spin-1/2 lattice, leading to the emergence of Floquet symmetry protected second-order topological phases. The formation of corner-localized 0 and π modes is verified, and the topological nature of these modes is established by deriving their associated topological invariants under special conditions.
Proceedings Paper
Computer Science, Theory & Methods
Shao-Hen Chiew, Leong-Chuan Kwek, Chee-Kong Lee
Summary: Conventional many-body quantum systems thermalize and lose information to the environment. However, closed quantum systems in the MBL phase retain local information. By simulating the dynamics and equilibration of temporal mutual information, we can distinguish between MBL and ergodic phases.
SUPERCOMPUTING FRONTIERS, SCFA 2022
(2022)
