Related papers: Progressive amorphization of GeSbTe phase-change m…
Phase change memory (PCM) devices are known to reduce in power consumption as the bit volume and contact area of their electrodes are scaled down. Here, we demonstrate two types of low-power PCM devices with lateral graphene ribbon…
It is demonstrated that persistent-photoconductivity (PPC), well-studied in lightly-doped semiconductors, is observable in GeSbTe compounds using infrared excitation at cryogenic temperatures. The low level of energy-flux necessary to…
We propose that the driving force of an ultrafast crystalline-to-amorphous transition in phase-change memory alloys are strained bonds existing in the (metastable) crystalline phase. For the prototypical example of GST, we demonstrate that…
Phase change materials are exploited in several enabling technologies such as storage class memories, neuromorphic devices and memories embedded in microcontrollers. A key functional property for these applications is the fast crystal…
Electronically reprogrammable photonic circuits based on phase-change chalcogenides present an avenue to resolve the von-Neumann bottleneck; however, implementation of such hybrid photonic-electronic processing has not achieved…
The phase change compound Ge$_2$Sb$_2$Te$_5$ (GST225) is exploited in advanced non-volatile electronic memories and in neuromorphic devices which both rely on a fast and reversible transition between the crystalline and amorphous phases…
The intrinsic nature of glass states and glass transitions at the atomic scale remain a fundamental open question in condensed-matter physics and materials science. By combining femtosecond electron diffraction with time-dependent…
The antimony-based chalcogenide Sb2Se3 is a rapidly emerging material for photonic phase change applications owing to its ultra-low optical losses at telecommunication wavelengths in both crystalline and amorphous phases. Here, we…
We suggest a phenomenological description of the photo-conversion in Ge-Sb-Te phase-change memory alloys from amorphous to crystalline phase which explains why both photo-excitation and high temperatures T > 160C are required for the…
Reconfigurable photonic systems featuring minimal power consumption are crucial for integrated optical devices in real-world technology. Current active devices available in foundries, however, use volatile methods to modulate light,…
Nonvolatile phase change random access memory (PCRAM) is regarded as one of promising candidates for emerging mass storage in the era of Big Data. However, relatively high programming energy hurdles the further reduction of power…
Energy-efficient programmable photonic integrated circuits (PICs) are the cornerstone of on-chip classical and quantum optical technologies. Optical phase shifters constitute the fundamental building blocks which enable these programmable…
Phase-change materials (PCMs) are increasingly recognised as promising platforms for tunable photonic devices due to their ability to modulate optical properties through solid-state phase transitions. Ultrathin and low-loss PCMs are highly…
We report on an inelastic (Raman) light scattering study of the local structure of amorphous GeTe films. A detailed analysis of the temperature-reduced Raman spectra has shown that appreciable structural changes occur as a function of…
We measure power dissipation in phase change memory (PCM) devices by scanning Joule ex-pansion microscopy (SJEM) with ~50 nm spatial and 0.2 K temperature resolution. The temperature rise in the Ge2Sb2Te5 (GST) is dominated by Joule…
Chalcogenide alloys are materials of interest for optical recording and non-volatile memories. We perform ab-initio molecular dynamics simulations aiming at shading light onto the structure of amorphous Ge2Sb2Te5 (GST), the prototypical…
We analyze, design and assess the performance of a reflective reconfigurable metasurface (MS) architecture for optical wireless communications. The device is based on the Ge-Sb-Te (GST225) phase-change material (PCM) alloy, thermally…
The synergy between metasurfaces and non-volatile phase change materials (PCMs) has created many reconfigurable photonic devices for applications in optical memory, optical computing and optical communications. But these advances have been…
This work investigates the problematic diffusion of metal atoms into phase change chalcogenides, which can destroy resonances in photonic devices. Interfaces between Ge2Sb2Te5 and metal layers were studied using X-ray reflectivity (XRR) and…
Resistance drift in phase change materials is characterized in amorphous phase change memory line-cells from 300 K to 125 K range and is observed to follow the previously reported power-law behavior with drift coefficients in the 0.07 to…