The Experts below are selected from a list of 52437 Experts worldwide ranked by ideXlab platform

Matthias Wuttig - One of the best experts on this subject based on the ideXlab platform.

  • Phase Change Materials for non volatile photonic applications
    Nature Photonics, 2017
    Co-Authors: Matthias Wuttig, Harish Bhaskaran, Thomas Taubner
    Abstract:

    Materials whose optical properties can be reconfigured are crucial for photonic applications such as optical memories. Phase-Change Materials offer such utility and here recent progress is reviewed.

  • Aging mechanisms in amorphous Phase-Change Materials
    Nature Communications, 2015
    Co-Authors: J.-y. Raty, Jennifer Luckas, Riccardo Mazzarello, Christophe Bichara, Wei Zhang, Matthias Wuttig
    Abstract:

    Aging is a ubiquitous phenomenon in glasses. In the case of Phase-Change Materials, it leads to a drift in the electrical resistance, which hinders the development of ultrahigh density storage devices. Here we elucidate the aging process in amorphous GeTe, a prototypical Phase-Change material, by advanced numerical simulations, photothermal deflection spectroscopy and impedance spectroscopy experiments. We show that aging is accompanied by a progressive Change of the local chemical order towards the crystalline one. Yet, the glass evolves towards a covalent amorphous network with increasing Peierls distortion, whose structural and electronic properties drift away from those of the resonantly bonded crystal. This behaviour sets Phase-Change Materials apart from conventional glass-forming systems, which display the same local structure and bonding in both Phases.

  • Phase Change Materials and Phase Change memory
    Mrs Bulletin, 2014
    Co-Authors: Simone Raoux, Matthias Wuttig, Feng Xiong, Eric Pop
    Abstract:

    Phase Change memory (PCM) is an emerging technology that combines the unique properties of Phase Change Materials with the potential for novel memory devices, which can help lead to new computer architectures. Phase Change Materials store information in their amorphous and crystalline Phases, which can be reversibly switched by the application of an external voltage. This article describes the advantages and challenges of PCM. The physical properties of Phase Change Materials that enable data storage are described, and our current knowledge of the Phase Change processes is summarized. Various designs of PCM devices with their respective advantages and integration challenges are presented. The scaling limits of PCM are addressed, and its performance is compared to competing existing and emerging memory technologies. Finally, potential new applications of Phase Change devices such as neuromorphic computing and Phase Change logic are outlined.

  • Hall mobility in amorphous Phase Change Materials
    2013
    Co-Authors: Matthias Kaes, A. Mantz, Haaf Volker, Martin Salinga, Matthias Wuttig
    Abstract:

    Measurements of the Hall mobility in thin films of as deposited amorphous Phase Change material are shown. By employing a sinusoidal variation of both the externally applied sample voltage and magnetic field at different frequencies the microvolt Hall signal can be very accurately detected with a lock-in method. The temperature dependence of the Hall mobility as well as aging effects are studied. The implications on steady state transport in amorphous Phase-Change Materials are presented by including thermopower measurements.

  • The Science and Technology of Phase Change Materials
    Zeitschrift für anorganische und allgemeine Chemie, 2012
    Co-Authors: Matthias Wuttig, Simone Raoux
    Abstract:

    Phase Change Materials are solids which are characterized by a unique combination of properties. They exist in an amorphous and a crystalline Phase with remarkably different optical and electrical properties caused by an unusual Change of bonding when the amorphous Phase is crystallized. It is possible to Change the Phase of such a material in very short times (nanoseconds) and repeatedly between the two Phases which makes Phase Change Materials ideal candidates for data storage. This paper reviews in detail the relationship between the bonding mechanisms and the resulting physical properties of Phase Change Materials. It describes the Change of bonding from ordinary covalent bonding in the amorphous Phase to resonance bonding in the crystalline Phase with additional disorder, resulting in unconventional physical properties of Phase Change Materials. These properties lead to the development of Phase Change data storage applications. Phase Change optical data storage, Phase Change random access memory, and emerging applications including neuromorphic computing are described with particular emphasis on material requirements and material engineering for Phase Change random access memory.

Murat Kenisarin - One of the best experts on this subject based on the ideXlab platform.

  • high temperature Phase Change Materials for thermal energy storage
    Renewable & Sustainable Energy Reviews, 2010
    Co-Authors: Murat Kenisarin
    Abstract:

    The development of energy saving technologies is very actual issue of present day. One of perspective directions in developing these technologies is the thermal energy storage in various industry branches. The review considers the modern state of art in investigations and developments of high-temperature Phase Change Materials perspective for storage thermal and a solar energy in the range of temperatures from 120 to 1000 °C. The considerable quantity of mixes and compositions on the basis of fluorides, chlorides, hydroxides, nitrates, carbonates, vanadates, molybdates and other salts, and also metal alloys is given. Thermophysical properties of potential heat storage salt compositions and metal alloys are presented. Compatibility of heat storage Materials (HSM) and constructional Materials have found its reflection in the present work. Data on long-term characteristics of some HSMs in the course of repeated cycles of fusion and solidification are analyzed. Article considers also other problems which should be solved for creation of commercial high-temperature heat storage devices with use of Phase Change Materials.

Tomohiro Akiyama - One of the best experts on this subject based on the ideXlab platform.

  • development of Phase Change Materials based microencapsulated technology for buildings a review
    Renewable & Sustainable Energy Reviews, 2011
    Co-Authors: V V Tyagi, S C Kaushik, S K Tyagi, Tomohiro Akiyama
    Abstract:

    Thermal energy storage (TES) systems using Phase Change material (PCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. Now the research is focus on suitable method to incorporate PCMs with building. There are several methods to use Phase Change Materials (PCMs) in thermal energy storage (TES) for different applications. Microencapsulation is one of the well known and advanced technologies for better utilization of PCMs with building parts, such as, wall, roof and floor besides, within the building Materials. Phase Change Materials based microencapsulation for latent heat thermal storage (LHTS) systems for building application offers a challenging option to be employed as effective thermal energy storage and a retrieval device. Since the particular interest in using microencapsulation PCMs for concrete and wall/wallboards, the specific research efforts on both subjects are reviewed separately. This paper presents an overview of the previous research work on microencapsulation technology for thermal energy storage incorporating the Phase Change Materials (PCMs) in the building applications, along with few useful conclusive remarks concluded from the available literature.

Arunachala M. Kannan - One of the best experts on this subject based on the ideXlab platform.

  • Recent developments in Phase Change Materials for energy storage applications: A review
    International Journal of Heat and Mass Transfer, 2019
    Co-Authors: Hassan Nazir, Francisco J. Bolivar Osorio, Marllory Isaza-ruiz, Mariah Batool, Xinhai Xu, K. Vignarooban, Patrick Phelan, Arunachala M. Kannan
    Abstract:

    In order to overcome the increasing demand–supply energy gap due to the rapid urbanization, labor productivity, consumerism and depletion of fossil fuel resources, there is a need for the development of technologies with renewable energy sources. Phase Change Materials are one of the most appropriate Materials for effective utilization of thermal energy from the renewable energy resources. As evident from the literature, development of Phase Change Materials is one of the most active research fields for thermal energy storage with higher efficiency. This review focuses on the application of various Phase Change Materials based on their thermophysical properties. In particular, the melting point, thermal energy storage density and thermal conductivity of the organic, inorganic and eutectic Phase Change Materials are the major selection criteria for various thermal energy storage applications with a wider operating temperature range. The strategy adopted in improving the thermal energy storage characteristics of the Phase Change Materials through encapsulation as well as nanoMaterials additives, are discussed in detail. Specifically, the future research trends in the encapsulation and nanoMaterials are also highlighted.

Thomas Taubner - One of the best experts on this subject based on the ideXlab platform.

  • Phase Change Materials for non volatile photonic applications
    Nature Photonics, 2017
    Co-Authors: Matthias Wuttig, Harish Bhaskaran, Thomas Taubner
    Abstract:

    Materials whose optical properties can be reconfigured are crucial for photonic applications such as optical memories. Phase-Change Materials offer such utility and here recent progress is reviewed.

  • Phase-Change Materials for non-volatile photonic applications
    Nature Photonics, 2017
    Co-Authors: M. Wuttig, Harish Bhaskaran, Thomas Taubner
    Abstract:

    Materials whose optical properties can be reconfigured are crucial for photonic applications such as optical memories. Phase-Change Materials offer such utility and here recent progress is reviewed. Phase-Change Materials (PCMs) provide a unique combination of properties. On transformation from the amorphous to crystalline state, their optical properties Change drastically. Short optical or electrical pulses can be utilized to switch between these states, making PCMs attractive for photonic applications. We review recent developments in PCMs and evaluate the potential for all-photonic memories. Towards this goal, the progress and existing challenges to realize waveguides with stepwise adjustable transmission are presented. Colour-rendering and nanopixel displays form another interesting application. Finally, nanophotonic applications based on plasmonic nanostructures are introduced. They provide reconfigurable, non-volatile functionality enabling manipulation and control of light. Requirements and perspectives to successfully implement PCMs in emerging areas of photonics are discussed.