Article
Materials Science, Multidisciplinary
Muhammad Shemyal Nisar, Shahid Iqbal, Sai-Wai Wong
Summary: Coding metasurfaces have been widely used in free space optics but not integrated photonic applications due to the lack of implementation methods. The use of low-loss phase change materials like Sb2S3 has made it possible to implement reprogrammable integrated metasurfaces. This paper presents Sb2S3 based 1-bit and 2-bit coding metasurfaces that can potentially be practically implemented and achieve functionalities such as beam focusing, beam splitting, and beam steering. This has potential applications in various fields including integrated photonic computational platforms.
RESULTS IN PHYSICS
(2023)
Article
Optics
Shoujun Zhang, Xieyu Chen, Kuan Liu, Haiyang Li, Yuehong Xu, Xiaohan Jiang, Yihan Xu, Qingwei Wang, Tun Cao, Zhen Tian
Summary: This article introduces a nonvolatile, reconfigurable, and dynamic Janus metasurface using phase-change material Ge2Se2Te5 (GST) in the terahertz (THz) regime. The reversible switching characteristic of GST on large areas is demonstrated, and a multiplex metasurface scheme is proposed. Various applications such as dynamic beam splitter, bifocal metalens, and switchable metalens/focusing optical vortex generators are designed and experimentally characterized. The development of multifunctional and compact THz devices can be facilitated by this scheme.
PHOTONICS RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Zhuoran Fang, Jiajiu Zheng, Abhi Saxena, James Whitehead, Yueyang Chen, Arka Majumdar
Summary: This study experimentally demonstrated the strong optical phase modulation and low optical loss of Sb2S3 at wavelengths of 750 nm and 1550 nm, showcasing the thermal stability of the Sb2S3-Si hybrid platform and an electrically tunable Sb2S3 integrated non-volatile microring switch with a high-contrast transmission state over 30 dB.
ADVANCED OPTICAL MATERIALS
(2021)
Article
Chemistry, Analytical
Muhammad Shemyal Nisar, Shahid Iqbal, Linjie Zhou
Summary: This paper presents a novel metasurface structure that utilizes phase change materials for active functionality. Through numerical simulations, the paper demonstrates the principle of beam steering by actively switching the phase of the implanted phase change material. The proposed architecture can enable on-chip transformation optics, mathematical operations, and information processing.
Article
Optics
Tianwei Wu, Marco Menarini, Zihe Gao, Liang Feng
Summary: Using spatial light modulator-based lithography-free programmable light transmission, we demonstrate optical switching and a basic photonic neural network. Integrated photonics is crucial for handling increasing data traffic due to its high speed, large bandwidth, and unlimited parallelism. This lithography-free paradigm allows for dynamic control of spatial-temporal modulations of the imaginary index, enabling tailored optical-gain distributions for desired photonic functionality. The resulting programmability and multifunctionality can revolutionize integrated photonic signal processing and enhance information-processing speed.
Letter
Optics
Jorge Parra, Juan Navarro-Arenas, Mariela Menghini, Maria Recaman, Jean Pierre-Locquet, Pablo Sanchis
Summary: This work presents an optical limiter based on silicon photonics with an ultracompact VO2/Si waveguide, featuring a thermal tunable threshold power of only about 3.5 mW and broadband spectral characteristics. It offers a new pathway towards integrated optical limiters for dense and low-power photonic integrated circuits.
Article
Engineering, Electrical & Electronic
Tamar Haimov, Koray Aydin, Jacob Scheuer
Summary: The proposed approach utilizes an active VO2 layer and a Bragg reflector to achieve dynamic holography at optical frequencies; a reconfigurable metasurface for tunable binary holography is proposed and analyzed; the device can also function as a broad-angle perfect absorber when tuned to the proper temperature.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Nanoscience & Nanotechnology
Sajjad Abdollahramezani, Hossein Taghinejad, Tianren Fan, Mahmood Reza Marzban, Ali A. Eftekhar, Ali Adibi
Summary: We present a hybrid device platform for creating an electrically reconfigurable metasurface by integrating plasmonic nanostructures with phase-change material GST. By changing the phase of GST, a wide range of responses can be achieved, leading to the realization of a broadband electrically tunable multifunctional metadevice.
Article
Engineering, Electrical & Electronic
Wenfei Li, Chao Qiu, Aimin Wu
Summary: Nonvolatile compact on-chip optical filters with a tunable spectral response have been developed for low-power optical communication systems and applications. By using phase change materials (PCMs) films on a phase-shifted Bragg grating (PSBG), the filter's key parameters, such as center wavelength and extinction ratio, can be simultaneously tuned for filtering or processing purposes. The filter achieved a 9 nm wavelength shift, and amplitude modulations of 16.1 dB in the transmission channel and 42.5 dB in the reflection channel, while keeping the center wavelength unchanged at 1550 nm. This compact device has a size of 500 nm x 31.9 μm and an insertion loss as low as -0.76 dB, making it ideal for large-scale integration. This development opens up new possibilities for next-generation low-power general-purpose photonic integrated circuits (PICs) and has potential applications in wavelength division multiplexing (WDM) systems, spectral shaping, and on-chip signal processors.
IEEE PHOTONICS JOURNAL
(2023)
Article
Optics
Haotian Tang, Liliana Stan, David A. Czaplewski, Xiaodong Yang, Jie Gao
Summary: Researchers demonstrated a wavelength-tunable infrared chiral metasurface integrated with phase-change material GST-225. The resonance wavelength of the metasurface can be tuned by varying the baking time above the phase transition temperature of GST-225. The chiroptical response of the metasurface was analyzed under left- and right-handed circularly polarized light illumination, and the photothermal effect was simulated to investigate the potential for circular polarization-controlled phase transition. This chiral metasurface with phase-change materials shows promise for applications in the infrared regime.
Article
Chemistry, Multidisciplinary
Ziquan Xu, Hao Luo, Huanzheng Zhu, Yu Hong, Weidong Shen, Jianping Ding, Sandeep Kaur, Pintu Ghosh, Min Qiu, Qiang Li
Summary: This study demonstrates a nonvolatile optically reconfigurable mid-infrared coding radiative metasurface, which allows for switching peak spectral emissivity values between low and high through laser pulses. Additionally, visible scattering patterns can be independently modulated, showing potential applications in anti-counterfeiting labels and other fields.
Review
Chemistry, Multidisciplinary
Ziyang Zhang, Hongyu Shi, Luyi Wang, Juan Chen, Xiaoming Chen, Jianjia Yi, Anxue Zhang, Haiwen Liu
Summary: This review introduces different methods to design reconfigurable metasurfaces, categorized by the techniques they use such as special materials, semiconductor components, and mechanical devices. The review compares these methods and discusses their advantages and disadvantages, as well as the challenges and possible future developments.
Article
Engineering, Electrical & Electronic
Zhuoran Fang, Rui Chen, Jiajiu Zheng, Arka Majumdar
Summary: The use of phase change materials in silicon photonics has been gaining attention due to their high refractive index contrast between two states, which can be reversibly switched and non-volatile. Progress has been made in developing photonic switches based on PCM for photonic integrated circuits, showing great potential for future applications in this field.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Review
Chemistry, Multidisciplinary
Omar A. M. Abdelraouf, Ziyu Wang, Hailong Liu, Zhaogang Dong, Qian Wang, Ming Ye, Xiao Renshaw Wang, Qi Jie Wang, Hong Liu
Summary: Metasurfaces, a 2D form of metamaterials, exhibit exotic abilities to tailor EM waves freely. By integrating various active materials and external stimuli, tunable metasurfaces offer substantial tunability and rich degrees of freedom in manipulating and controlling EM waves.
Article
Nanoscience & Nanotechnology
Isaac O. Oguntoye, Siddharth Padmanabha, Max Hinkle, Thalia Koutsougeras, Adam J. Ollanik, Matthew D. Escarra
Summary: Efficient and dynamic light manipulation at small scale can be achieved through active optical metasurfaces, which offer compact design and low power consumption. In this study, a dynamically tunable metasurface based on vanadium dioxide is demonstrated, allowing independent control of amplitude and phase without mechanical parts. The nanofabrication of vanadium dioxide enables computationally predicted continuously tuned amplitude and phase modulation. Experimental results show stable intermediate states and repeated modulation without degradation, indicating the potential for reprogrammable optical functionality.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Joe Shields, Carlota Ruiz de Galarreta, Jacopo Bertolotti, C. David Wright
Summary: Materials with thermally tunable refractive indices have potential for developing active optical metasurfaces for controlling light properties. However, in situ electrical switching through resistive heaters is crucial for viable technology. Noble metals like gold and silver are needed for their conductivity and high melting points, but their diffusion into phase-change materials and dielectric resonators can degrade optical performance. This study introduces a hybrid dielectric/plasmonic metasurface architecture to address this issue and shows how incorporating ultrathin Si3N4 barrier layers can overcome degradation caused by metal diffusion. Through this research, the importance of noble metal diffusion in thermally tunable metasurfaces is clarified and solutions are proposed to advance phase-change metasurface technology towards real-world applications.
Article
Physics, Applied
E. Gemo, J. Faneca, S. G. -C. Carrillo, A. Baldycheva, W. H. P. Pernice, H. Bhaskaran, C. D. Wright
Summary: Chalcogenide phase-change materials have sparked scientific and industrial interest, especially in non-volatile optical and electronic storage devices. Recent research focuses on integrating these materials with photonic circuits for enhanced optical computing capabilities. Plasmonics presents a solution to overcome limitations in reading nanometric volumes of phase-change material in conventional integrated photonic systems.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Nanoscience & Nanotechnology
Carlota Ruiz de Galarreta, Noemi Casquero, Euan Humphreys, Jacopo Bertolotti, Javier Solis, C. David Wright, Jan Siegel
Summary: This study presents a novel single-step process for the rapid fabrication of high-performance mid- and long-wave infrared EOT metasurfaces using ultrafast direct laser writing. By carefully controlling three key experimental parameters, the optical characteristics of the extraordinary transmission effect can be precisely controlled. The fabricated devices exhibit high performance, flexibility, and reliability, demonstrating the potential for mass production of metasurfaces with on-demand optical properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Joaquin Faneca, Sebastian Meyer, F. Y. Gardes, Dmitry N. Chigrin
Summary: In order to effectively control the state of an active integrated photonic component based on chalcogenide phase change materials, a low voltage efficient microheater is required. A graphene-based microheater is designed and a detailed investigation of the heater parameters is conducted to optimize the switching performance. The switching capabilities of the proposed design are demonstrated through self-consistent multiphysics simulation.
OPTICAL MATERIALS EXPRESS
(2022)
Article
Multidisciplinary Sciences
Syed Ghazi Sarwat, Frank Brueckerhoff-Plueckelmann, Santiago Garcia-Cuevas Carrillo, Emanuele Gemo, Johannes Feldmann, Harish Bhaskaran, C. David Wright, Wolfram H. P. Pernice, Abu Sebastian
Summary: With the digitization of modern life and scientific tools, the generation of data is growing exponentially, requiring fast and efficient statistical processing. This paper introduces a novel computational paradigm through the development of an integrated phase-change photonics engine. By exploiting the properties of phase-change cells and optics, the engine enables fully parallel and colocated temporal correlation detection computations. Experimental demonstrations on Twitter and data centers showcase the use of high-speed integrated photonics in accelerating statistical analysis methods.
Article
Physics, Applied
Noemi Casquero, Carlota Ruiz de Galarreta, Yasser Fuentes-Edfuf, Javier Solis, C. David Wright, Jan Siegel
Summary: In this study, the melting and solidification dynamics of germanium upon ns and fs laser pulse irradiation were investigated using real-time pump-probe experiments and finite element calculations. The results show significant differences in the melting and solidification velocities for different pulse durations and fluences, as well as variations in the maximum thickness of the molten layer. High precision measurements using fs microscopy also revealed large differences in the melt-in process.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Review
Chemistry, Analytical
Frederic Gardes, Afrooz Shooa, Greta De Paoli, Ilias Skandalos, Stefan Ilie, Teerapat Rutirawut, Wanvisa Talataisong, Joaquin Faneca, Valerio Vitali, Yaonan Hou, Thalia Dominguez Bucio, Ioannis Zeimpekis, Cosimo Lacava, Periklis Petropoulos
Summary: This review presents recent advances in silicon nitride photonic integrated circuits. It discusses the available material deposition techniques and their capabilities, and further explores the functionalization of the platform for nonlinear processing, optical modulation, nonvolatile optical memories, and integration with III-V materials.
Article
Chemistry, Multidisciplinary
George Braid, Carlota Ruiz de Galarreta, Andrew Comley, Jacopo Bertolotti, C. David Wright
Summary: This study designs and simulates active meta-lenses that can control the numerical aperture of a lens using chalcogenide phase-change materials. Operating at a wavelength of 3000 nm, the devices can increase the numerical aperture by up to 1.85 times, and demonstrate scalability towards shorter wavelengths in the visible spectrum.
Article
Materials Science, Multidisciplinary
Lyubov Kotova, Linar A. Altynbaev, Maria O. Zhukova, Bogdan R. Borodin, Vladimir P. Kochereshko, Anna Baldycheva, Benjamin T. Hogan
Summary: Unusual optical anisotropy was observed in hexagonal boron nitride thin films produced via ultrasonication. Statistical analysis revealed an ordered particle density distribution corresponding to the observed optical axis.
Article
Materials Science, Multidisciplinary
Euan Humphreys, Jacopo Bertolotti, Carlota Ruiz de Galarreta, Noemi Casquero, Jan Siegel, C. David Wright
Summary: Periodic arrays of sub-wavelength-scale holes in plasmonic metal films enable resonant transmission peaks through the extraordinary optical transmission (EOT) effect. By incorporating a phase-change material (PCM) layer in the EOT device, active control of the spectral position of these transmission peaks is achieved. The switching between amorphous and crystalline states of the PCM layer leads to a shift in the resonance, enabling potential applications in active filtering, sensing (e.g., multispectral sensing), and signal modulation. This article focuses on the design, fabrication, and characterization of active EOT devices targeting various important regions in the optical spectrum.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Physics, Applied
K. G. Fripp, Y. Au, A. V. Shytov, V. V. Kruglyak
Summary: We investigate chiral magnonic resonators as building blocks for artificial neural networks. Through micromagnetic simulations and analytical modeling, we demonstrate that the confined spin-wave modes in the resonators exhibit a highly nonlinear response due to energy concentration. This nonlinear effect can be utilized to implement artificial neurons in a network.
APPLIED PHYSICS LETTERS
(2023)
Article
Optics
Miguel Alvarez-Alegria, Carlota de Ruiz de Galarreta, Jan Siegel
Summary: Direct Laser Interference Patterning (DLIP) is a versatile technique for fabricating periodic micro- to nanometric scale structures. This study combines deep-ultraviolet (UV) DLIP with real-time optical reflectivity and diffraction techniques to investigate the formation dynamics of grating structures with periods down to 740 nm. The results reveal the importance of considering Marangoni convection and thermocapillary waves in the formation process of 3D structures. This technique has the potential to unravel the formation dynamics of various periodic structures in different materials.
LASER & PHOTONICS REVIEWS
(2023)
Article
Materials Science, Multidisciplinary
Joe Shields, Carlota Ruiz De Galarreta, Harry Penketh, Yat-Yin Au, Jacopo Bertolotti, C. David Wright
Summary: A phase-change material based, thin-film, amplitude-only spatial light modulator is introduced, which modulates the amplitude of incident light without affecting its optical phase. This is achieved by using a thin-film device with a switchable GeTe phase-change layer. Experimental results show that the reflected intensity can be modulated up to 38% with a small average phase difference. The ability of phase-change materials to switch on a sub-microsecond timescales suggests the potential of this modulator in various applications, such as wavefront shaping, communications, sensing, and imaging.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Danil W. Boukhvalov, Vladimir Yu. Osipov, Benjamin Thomas Hogan, Anna Baldycheva
Summary: We propose new models to accurately determine the optical properties of nitrogen-free carbon quantum dots (CQDs) with ordered graphene layered structures. These models are validated against experimental results for CQDs from literature review, and can be applied to CQDs with varied sizes and oxygen contents. The blue fluorescent emission of nitrogen-free CQDs is found to be associated with oxidised areas on the periphery of the graphene sheet or non-functionalised islands of carbon in the centres of oxidised graphene sheets. Additionally, larger and/or less symmetric non-functionalised regions contribute to green and red fluorescent emission. The models also show that the bandgaps and photoluminescence of CQDs are not affected by out-of-plane corrugation or spacing between islands.
Article
Chemistry, Physical
Galyna Dovbeshko, Olena Gnatyuk, Andrej Dementjev, Danielis Rutkauskas, Evgeniya Kovalska, Anna Baldycheva, Oleksii Ilchenko, Dmytro Krasnenkov, Tommi Kaplas
Summary: This study compares the Raman and CARS patterns of DNA molecules deposited on graphene or glass substrates, finding that in DNA CARS spectra, vibrational resonances are red-shifted and exhibit new features in the high-frequency region. The research demonstrates the utility of CARS imaging for visualizing and characterizing DNA molecules deposited on graphene.
