Hasil untuk "Optics. Light"

Martin Weigert, Uwe Schmidt, Tobias Boothe et al.

P. Lodahl, S. Mahmoodian, S. Stobbe

Photonic nanostructures provide means of tailoring the interaction between light and matter and the past decade has witnessed a tremendous experimental and theoretical progress in this subject. In particular, the combination with semiconductor quantum dots has proven successful. This manuscript reviews quantum optics with excitons in single quantum dots embedded in photonic nanostructures. The ability to engineer the light-matter interaction strength in integrated photonic nanostructures enables a range of fundamental quantum-electrodynamics experiments on, e.g., spontaneous-emission control, modified Lamb shifts, and enhanced dipole-dipole interaction. Furthermore, highly efficient single-photon sources and giant photon nonlinearities may be implemented with immediate applications for photonic quantum-information processing. The review summarizes the general theoretical framework of photon emission including the role of dephasing processes, and applies it to photonic nanostructures of current interest, such as photonic-crystal cavities and waveguides, dielectric nanowires, and plasmonic waveguides. The introduced concepts are generally applicable in quantum nanophotonics and apply to a large extent also to other quantum emitters, such as molecules, nitrogen vacancy ceters, or atoms. Finally, the progress and future prospects of applications in quantum-information processing are considered.

Andrea Alú

Hiroyuki Fujiwara, Download Here

U. Leonhardt

A. Wallraff, D. Schuster, A. Blais et al.

The interaction of matter and light is one of the fundamental processes occurring in nature, and its most elementary form is realized when a single atom interacts with a single photon. Reaching this regime has been a major focus of research in atomic physics and quantum optics for several decades and has generated the field of cavity quantum electrodynamics. Here we perform an experiment in which a superconducting two-level system, playing the role of an artificial atom, is coupled to an on-chip cavity consisting of a superconducting transmission line resonator. We show that the strong coupling regime can be attained in a solid-state system, and we experimentally observe the coherent interaction of a superconducting two-level system with a single microwave photon. The concept of circuit quantum electrodynamics opens many new possibilities for studying the strong interaction of light and matter. This system can also be exploited for quantum information processing and quantum communication and may lead to new approaches for single photon generation and detection.

S. A. Collins

E. Yablonovitch

Y. Akahane, T. Asano, B. Song et al.

L. Bergé, S. Skupin, R. Nuter et al.

Modern laser sources nowadays deliver ultrashort light pulses reaching few cycles in duration and peak powers exceeding several terawatt (TW). When such pulses propagate through optically transparent media, they first self-focus in space and grow in intensity, until they generate a tenuous plasma by photo-ionization. For free electron densities and beam intensities below their breakdown limits, these pulses evolve as self-guided objects, resulting from successive equilibria between the Kerr focusing process, the chromatic dispersion of the medium and the defocusing action of the electron plasma. Discovered one decade ago, this self-channeling mechanism reveals a new physics, widely extending the frontiers of nonlinear optics. Implications include long-distance propagation of TW beams in the atmosphere, supercontinuum emission, pulse shortening as well as high-order harmonic generation. This review presents the landmarks of the 10-odd-year progress in this field. Particular emphasis is laid on the theoretical modeling of the propagation equations, whose physical ingredients are discussed from numerical simulations. The dynamics of single filaments created over laboratory scales in various materials such as noble gases, liquids and dielectrics reveal new perspectives in pulse shortening techniques. Far-field spectra provide promising diagnostics. Attention is also paid to the multifilamentation instability of broad beams, breaking up the energy distribution into small-scale cells along the optical path. The robustness of the resulting filaments in adverse weathers, their large conical emission exploited for multipollutant remote sensing, nonlinear spectroscopy and the possibility of guiding electric discharges in air are finally addressed on the basis of experimental results.

Na Ji, D. Milkie, E. Betzig

Y. Lai, J. Ng, Huanyang Chen et al.

We propose to use transformation optics to generate a general illusion such that an arbitrary object appears to be like some other object of our choice. This is achieved by using a remote device that can transform the scattered light outside a virtual boundary into that of the object chosen for the illusion, irrespective of the profile and direction of the incident light. This type of illusion device also enables people to see through walls. Our work extends the concept of cloaking as a special form of illusion to the wider realm of illusion optics.

T. Popmintchev, Ming-Chang Chen, P. Arpin et al.

Zahra Sabzevari, Maryam Bahreini

Graphene-enhanced Raman spectroscopy (GERS) is a new method for enhancing Raman spectra based on chemical mechanisms. This article explores three different methods for producing graphene oxide-based substrates to enhance the Raman signal. The first substrate was prepared by spraying a graphene oxide suspension with distilled water onto a glass slide. The second substrate was prepared using graphene oxide powder and ethanol suspension and then sprayed onto a glass slide. The third substrate was prepared by spin-coating a graphene oxide suspension with distilled water onto a glass slide. Rhodamine 6G (R6G) was used to investigate the GERS effect on these three substrates. After depositing the R6G solution on the graphene-based substrates, the enhancement of Raman signals was compared. The experimental results showed that the Raman spectra were most enhanced using the substrate made by the third method.

Junwoo Park, Nataliya Sokolovska, Clément Cabriel et al.

In recent years, the segmentation of short molecular trajectories with varying diffusive properties has drawn particular attention of researchers, since it allows studying the dynamics of a particle. In the past decade, machine learning methods have shown highly promising results, also in changepoint detection and segmentation tasks. Here, we introduce a novel iterative method to identify the changepoints in a molecular trajectory, i.e. frames, where the diffusive behavior of a particle changes. A trajectory in our case follows a fractional Brownian motion and we estimate the diffusive properties of the trajectories. The proposed Bottom-up iterative anomalous diffusion detector (BI-ADD) combines unsupervised and supervised learning methods to detect the changepoints. Our approach can be used for the analysis of molecular trajectories at the individual level and also be extended to multiple particle tracking, which is an important challenge in fundamental biology. We validated BI-ADD in various scenarios within the framework of the 2nd anomalous diffusion challenge 2024 dedicated to single particle tracking. Our method is implemented in Python and is publicly available for research purposes.

Wenhao Wang, Long Wang, Qianqian Fu et al.

Color as an indispensable element in our life brings vitality to us and enriches our lifestyles through decorations, indicators, and information carriers. Structural color offers an intriguing strategy to achieve novel functions and endows color with additional levels of significance in anti-counterfeiting, display, sensor, and printing. Furthermore, structural colors possess excellent properties, such as resistance to extreme external conditions, high brightness, saturation, and purity. Devices and platforms based on structural color have significantly changed our life and are becoming increasingly important. Here, we reviewed four typical applications of structural color and analyzed their advantages and shortcomings. First, a series of mechanisms and fabrication methods are briefly summarized and compared. Subsequently, recent progress of structural color and its applications were discussed in detail. For each application field, we classified them into several types in terms of their functions and properties. Finally, we analyzed recent emerging technologies and their potential for integration into structural color devices, as well as the corresponding challenges.

Amir Namiq Hassan, Mohammad Ali Haddad, Abbas Behjat et al.

Abstract Nonlinear optics (NLO) and its applications have attracted increasing research interest in recent years owing to their contribution to the development of photonic technology. Accordingly, in this study, we investigated the NLO response of pumpkin seed oil using the spatial self-phase modulation (SSPM) method. Significant NLO characteristics have been experimentally studied at $$405\,{\text{nm}}$$ 405 nm and $$532\,{\text{nm}}$$ 532 nm continuous wave (CW) laser wavelengths, yielding second-order nonlinear refractive index ( $$n_{2,\,th}$$ n 2 , t h ) values of $$6.54 \times 10^{ - 5} \,{{{\text{cm}}^{2} } \mathord{\left/ {\vphantom {{{\text{cm}}^{2} } W}} \right. \kern-0pt} W}$$ 6.54 × 10 - 5 cm 2 / W and $$2.73 \times 10^{ - 5} \,{{{\text{cm}}^{2} } \mathord{\left/ {\vphantom {{{\text{cm}}^{2} } W}} \right. \kern-0pt} W}$$ 2.73 × 10 - 5 cm 2 / W , respectively. The findings suggest that the absorption of the material leads to higher optical nonlinearity at shorter wavelengths owing to higher thermal effects. Furthermore, we implemented a light-controlled-light system based on the spatial cross-phase modulation (SXPM) technique employing pumpkin seed oil. We successfully achieved all-optical switching by designing the 'ON' and 'OFF' modes. The results of this study can be considered for the future development of NLO applications. Moreover, our work investigates the potential of pumpkin seed oil for designing low-cost and high-efficiency NLO devices, and this contribution opens up a novel practical avenue for oil-based optical devices.

Volatier Jean-Baptiste, Beaussier Stephane J., Druart Guillaume et al.

In this article we describe the implementation of Freeform Optics Raytracer with Manufacturable Imaging Design cApaBiLitiEs (FORMIDABLE): an optical design library capable of simulating optical systems by ray-tracing. Optical performance can be quantified and optimised using third-party optimisation algorithms. Compared to available commercial optical design software and similarly to fast accurate NURBS optimization (FANO), our code can simulate and optimise Non-uniform rational B-Spline (NURBS). It also implements generalized differential capabilities that allows faster convergence compared to state-of-the-art. The implementation of FORMIDABLE and its innovative capabilities are described and illustrated with a representative case-study. The source code is available to eligible third-parties under the ECSL licence.

Michael Nickerson, Bowen Song, Jim Brookhyser et al.

A 16-channel optical phased array is fabricated on a gallium arsenide photonic integrated circuit platform with a low-complexity process. Tested with a 1064 nm external laser, the array demonstrates 0.92° beamwidth, 15.3° grating-lobe-free steering range, and 12 dB sidelobe level. Based on a reverse biased p-i-n structure, component phase modulators are 3 mm long with DC power consumption of less than 5 $μ$W and greater than 770 MHz electro-optical bandwidth. Individual 4-mm-long phase modulators based on the same structure demonstrate single-sided V$π{\cdot}$L modulation efficiency ranging from 0.5 V${\cdot}$cm to 1.23 V${\cdot}$cm when tested at wavelengths from 980 nm to 1360 nm.

George Winstone, Alexey Grinin, Mishkat Bhattacharya et al.

Optomechanics, the study of the mechanical interaction of light with matter, has proven to be a fruitful area of research that has yielded many notable achievements, including the direct detection of gravitational waves in kilometer-scale optical interferometers. Light has been used to cool and demonstrate quantum control over the mechanical degrees of freedom of individual ions and atoms, and more recently has facilitated the observation of quantum ``mechanics'' in objects of larger mass, even at the kg-scale. Optical levitation, where an object can be suspended by radiation pressure and largely decoupled from its environment, has recently established itself as a rich field of study, with many notable results relevant for precision measurement, quantum information science, and foundational tests of quantum mechanics and fundamental physics. This article provides a survey of several current activities in field along with a tutorial describing associated key concepts and methods, both from an experimental and theoretical approach. It is intended as a resource for junior researchers who are new to this growing field as well as beginning graduate students. The tutorial is concluded with a perspective on both promising emerging experimental platforms and anticipated future theoretical developments.