Physics and Astronomy, Acoustics and Ultrasonics, Electrical and Electronic Engineering
61
Scopus Publications
Scopus Publications
Geometric Phase Metasurface for Lens Antenna System With High Polarisation Purity and Efficiency Alexia Moreno‐Peñarrubia, Sheyly Ortiz‐Reyes, Jorge Teniente, Sergei Kuznetsov, Bakhtiyar Orazbayev, Miguel Beruete Iet Microwaves Antennas and Propagation, 2026 This work presents a millimetre‐wave antenna–metalens system based on the Pancharatnam–Berry phase principle. The setup includes a circularly polarised horn antenna combined with bi‐layer metalens optimised for 87 GHz operation. This arrangement achieves an axial ratio (AR) of 0.5 dB, directivity up to 34.7 dB–surpassing the original horn antenna over 17 dB–an aperture efficiency of 47% and exhibits a narrow beamwidth. The system operates from 82 to 95 GHz with an AR below 2 dB, directivity over 32 dB and aperture efficiency exceeding 30%. Additionally, the same metalens is characterised at 75 and 105 GHz, where the focal shift associated with frequency scaling is observed, yet directivity remains around 32 dB and AR below 3 dB. Notably, the aperture efficiency remains approximately 30% for the full frequency range, demonstrating the inherent frequency tolerance of the Pancharatnam–Berry phase implementation.
Honeycomb-Inspired Metamaterial for Tactile Sensors with Variable Stiffness Rustam Chibar, Valeriya Kostyukova, Soibkhon Khajikhanov, Daryn Kenzhebek, Altay Zhakatayev, Bakhtiyar Orazbayev, Zhanat Kappassov IEEE Sensors Journal, 2025 The material’s stiffness plays a crucial role in tactile sensors and stiffness controllers of robot joints, facilitating safe and effective robot–environment interactions. Conventional controllers or sensors require a priori information about stiffness modulation to efficiently control environmental collisions and reduce their detrimental effects. Therefore, such inflexibility of real-time stiffness variation may cause instability if the dynamic mechanical system (a mass-spring-damper) changes during execution. In this article, we tackle the problem using a honeycomb metamaterial with a tunable stiffness to design a tactile sensor capable of detecting physical contact with low- and high-impact forces. We experimentally demonstrate that dynamic modification of the honeycomb structure reduces the maximum impact force by <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\approx$ </tex-math></inline-formula>30%, mitigating the rapid collision with the environment during contact detection. The results show that the honeycomb attachment allows for a more precise and controlled impact with varying degrees of energy and momentum transfer. The honeycomb attachment can be a valuable tool for grasping, explosive motion generation, and tactile sensing, requiring low-or-high-impact and controllable contact. Our study highlights the potential of using negative stiffness honeycomb (NSH) structures to improve the functionality of tactile sensors.
In the quest of lossless slow light at surface plasmons Korlan Ziyatkhan, Bakhtiyar Orazbayev, Constantinos Valagiannopoulos Scientific Reports, 2024 Surface plasmons, namely, the waves guided at the boundaries between metals and dielectrics, are employed in a variety of engineering applications, spanning from photodetection and near-field scanning to biosensing and medical imaging. The spatial confinement of this effect makes it ideal for a quest towards low-loss guiding of slow light along the interfaces of similar heterostructures. Numerous pairs of materials are considered to determine the conditions for the emergence of strong surface waves, once the visible-light frequency is selected to secure minimum phase velocity or minimum propagation losses. The reported results can offer multiple optimal alternatives in the forward and inverse design of photonic components calling for high-intensity, low-loss slow light being guided across two-dimensional boundaries.
Wave-momentum shaping for moving objects in heterogeneous and dynamic media Bakhtiyar Orazbayev, Matthieu Malléjac, Nicolas Bachelard, Stefan Rotter, Romain Fleury Nature Physics, 2024 Light and sound waves can move objects through the transfer of linear or angular momentum, which has led to the development of optical and acoustic tweezers, with applications ranging from biomedical engineering to quantum optics. Although impressive manipulation results have been achieved, the stringent requirement for a highly controlled, low-reverberant and static environment still hinders the applicability of these techniques in many scenarios. Here we overcome this challenge and demonstrate the manipulation of objects in disordered and dynamic media by optimally tailoring the momentum of sound waves iteratively in the far field. The method does not require information about the object’s physical properties or the spatial structure of the surrounding medium but relies only on a real-time scattering matrix measurement and a positional guide-star. Our experiment demonstrates the possibility of optimally moving and rotating objects to extend the reach of wave-based object manipulation to complex and dynamic scattering media. We envision new opportunities for biomedical applications, sensing and manufacturing.
Trapping EM Power by Hollow Cylinders Abay Koshkimbay, Ildar Yusupov, Bakhtiyar Orazbayev, Alexey Slobozhanyuk, Constantinos Valagiannopoulos IEEE Transactions on Microwave Theory and Techniques, 2024 Thin tubes can trap the electromagnetic (EM) energy, emitted wirelessly from a near-field source. The optimal dimensions of these hollow cylinders are determined for an extensive range of complex permittivities characterizing their material and the reported power enhancement is found practically independent of the antenna location. The spatial distribution of the signal reveals the reshaping in the paths of incoming rays and unveils the nature of the developed resonances in the vicinity of the photonic tubes, for both wave polarizations. The concept is experimentally demonstrated at the UHF band with the use of dense dielectric claddings; enhancement up to two orders of magnitude is recorded. The presented results constitute limits in terms of the EM energy accumulation for a simple configuration and, thus, can be utilized in various wireless power transfer (WPT) applications.
Moving objects in diverse media through wave momentum manipulation B. Orazbayev, M. Malléjac, N. Bachelard, S. Rotter, R. Fleury 2024 18th International Congress on Artificial Materials for Novel Wave Phenomena Metamaterials 2024, 2024 In this paper, we experimentally demonstrate the ability to move an object in disordered and dynamic media by using acoustic waves for transferring linear or angular momentum to the object. In contrast to the remarkable results that have been achieved in optical or acoustical tweezers, our approach overcomes the strict requirements for the environment, such as a tightly controlled environment with minimal reverberation and static conditions. Furthermore, we demonstrate that knowledge of the physical attributes of objects or the composition of the surrounding medium is not needed. Instead, we acquire scattering information and the position of the object to adjust the incident wavefronts iteratively as it moves, and operate only from the far field. Finally, we demonstrate the method’s robustness to substantial alterations in the scattering medium.
VibroTouch: Active Tactile Sensor for Contact Detection and Force Sensing via Vibrations Danissa Sandykbayeva, Zhanat Kappassov, Bakhtiyar Orazbayev Sensors, 2022 Accurate and fast contact detection between a robot manipulator and objects is crucial for safe robot–object and human–robot interactions. Traditional collision detection techniques relied on force–torque sensors and Columb friction cone estimation. However, the strain gauges used in the conventional force sensors require low-noise and high-precision electronics to deliver the signal to the final user. The Signal-to-Noise Ratio (SNR) in these devices is still an issue in light contact detection. On the other hand, the Eccentric Rotating Mass (ERM) motors are very sensitive to subtle touch as their vibrating resonant state loses immediately. The vibration, in this case, plays a core role in triggering the tactile event. This project’s primary goal is to use generated and received vibrations to establish the scope of object properties that can be obtained through low-frequency generation on one end and Fourier analysis of the accelerometer data on the other end. The main idea behind the system is the phenomenon of change in vibration propagation patterns depending on the grip properties. Moreover, the project’s original aim is to gather enough information on vibration feedback on objects of various properties and compare them. These data sets are further analyzed in terms of frequency and applied grip force correlations in order to prepare the ground for pattern extraction and recognition based on the physical properties of an object.
PhotoElasticFinger: Robot Tactile Fingertip Based on Photoelastic Effect Dinmukhammed Mukashev, Nurdaulet Zhuzbay, Ainur Koshkinbayeva, Bakhtiyar Orazbayev, Zhanat Kappassov Sensors, 2022 The sense of touch is fundamental for a one-to-one mapping between the environment and a robot that physically interacts with the environment. Herein, we describe a tactile fingertip design that can robustly detect interaction forces given data collected from a camera. This design is based on the photoelastic effect observed in silicone matter. Under the force applied to the silicone rubber, owing to the stress-induced birefringence, the light propagating within the silicone rubber is subjected to the angular phase shift, where the latter is proportional to the increase in the image brightness in the camera frames. We present the calibration and test results of the photoelastic sensor design on a bench using a robot arm and with a certified industrial force torque sensor. We also discuss the applications of this sensor design and its potential relationship with human mechano-transduction receptors. We achieved a force sensing range of up to 8 N with a force resolution of around 0.5 N. The photoelastic tactile fingertip is suitable for robot grasping and might lead to further progress in robust tactile sensing.
Effect of mechanical nonlinearity on the electromagnetic response of a microwave tunable metamaterial Rayehe Karimi Mahabadi, Taha Goudarzi, Romain Fleury, Bakhtiyar Orazbayev, Reza Naghdabadi Journal of Physics D Applied Physics, 2022 Tunable metamaterials functionalities change in response to external stimuli. Mechanical deformation is known to be an efficient approach to tune the electromagnetic response of a deformable metamaterial. However, in the case of large mechanical deformations, which are usually required to fully exploit the potential of the tunable metamaterials, the linear elastic mechanical analysis is no longer suitable. Nevertheless, nonlinear mechanical analysis is missing in the studies of mechanically tunable metamaterials. In this paper, we study the importance of considering nonlinearity in mechanical behavior when analyzing the response of a deformable metamaterial and its effects on electromagnetic behavior. We consider a microwave metamaterial formed by copper four-cut split ring resonators on a Polydimethylsiloxane (PDMS) substrate. Applying both displacement and force stimuli, we show that when the deformation is large, more than 10 percent strain, the use of nonlinear analysis considering the geometrical and material nonlinearities is imperative. We further show that the discrepancies between the linear and nonlinear analyses appear in overestimating the stress, underestimating the tunability of the metamaterial responses, and mispredicting the negative permeability regions.
Polarization Conversion Metalens for millimeter waves International Conference on Metamaterials Photonic Crystals and Plasmonics, 2022
Graphene-dielectric metamaterial for beam steering B. Orazbayev, M. Beruete, I. Khromova 2016 10th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics Metamaterials 2016, 2016
W-band hybrid wood zone plate fishnet metalens B. Orazbayev, M. Navarro-Cia, M. Beruete 2016 10th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics Metamaterials 2016, 2016
Ultrathin carpet cloak based on ring resonators B. Orazbayev, N. Mohammadi Estakhri, M. Beruete, A. Alu 2016 10th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics Metamaterials 2016, 2016
V-band reference-phase-based zoned fishnet metalens V. Pacheco-Pena, B. Orazbayev, M. Beruete, M. Navarro-Cia, I. V. Minin, O. V. Minin 2016 Usnc Ursi Radio Science Meeting Joint with AP S Symposium Usnc Ursi 2016 Proceedings, 2016
A quasi-spiral antenna for THz - IR dual-band sensors Alicia E. Torres-Garcia, Bakhtiyar Orazbayev, Ramon Gonzalo, Inigo Ederra 2016 Global Symposium on Millimeter Waves Gsmm 2016 and ESA Workshop on Millimetre Wave Technology and Applications, 2016
Metasurface-based ultrathin carpet cloak B. Orazbayev, N. Mohammadi Estakhri, M. Beruete, A. Alu 2016 10th European Conference on Antennas and Propagation Eucap 2016, 2016
Soret lens-antenna based on the fishnet metamaterial B. Orazbayev, M. Beruete, V. Pacheco-Pena, G. Crespo, J. Teniente, M. Navarro-Cia 2016 10th European Conference on Antennas and Propagation Eucap 2016, 2016
Zoning technique for a broadband fishnet metamaterial lens Bakhtiyar Orazbayev, Victor Pacheco-Pena, Victor Torres, Miguel Beruete, Miguel Navarro-Cia Irmmw Thz 2015 40th International Conference on Infrared Millimeter and Terahertz Waves, 2015
Epsilon-near-zero lens for beamshaping of sub-terahertz waves Victor Torres, Victor Pacheco-Pena, Bakhtiyar Orazbayev, Jorge Teniente, Miguel Beruete, Miguel Navarro-Cia, Mario Sorolla, Nader Engheta Irmmw Thz 2015 40th International Conference on Infrared Millimeter and Terahertz Waves, 2015
144 GHz epsilon-near-zero lens antenna Víctor Torres, Víctor Pacheco-Peña, Bakhtiyar Orazbayev, Jorge Teniente, Miguel Beruete, Miguel Navarro-Cía, Mario Sorolla, Nader Engheta 2015 Usnc Ursi Radio Science Meeting Joint with AP S Symposium Usnc Ursi 2015 Proceedings, 2015
Zoned fishnet metamaterial lens with millimetre-wave dual-band response 2015 9th European Conference on Antennas and Propagation Eucap 2015, 2015
High gain flat sinusoidal Bull's Eye leaky millimetre-wave antenna 2015 9th European Conference on Antennas and Propagation Eucap 2015, 2015
144 GHz epsilon-near-zero metamaterial lens 2015 9th European Conference on Antennas and Propagation Eucap 2015, 2015
Slimming the fishnet metamaterial lens V. Pacheco-Pena, B. Orazbayev, V. Torres, M. Beruete, M. Navarro-Cia 8th European Conference on Antennas and Propagation Eucap 2014, 2014
