Implication of the double-gating mode in a hybrid photon counting detector for measurements of transient heat conduction in GaAs/AlAs superlattice structures.

Understanding and control of thermal transport in solids at the nanoscale are crucial in engineering and enhance the properties of a new generation of optoelectronic, thermoelectric and photonic devices. In this regard, semiconductor superlattice structures provide a unique platform to study phenomena associated with phonon propagations in solids such as heat conduction. Transient X-ray diffraction can directly probe atomic motions and therefore is among the rare techniques sensitive to phonon dynamics in condensed matter.

Hybrid pixel direct detector for electron energy loss spectroscopy.

We characterize a hybrid pixel direct detector and demonstrate its suitability for electron energy loss spectroscopy (EELS). The detector has a large dynamic range, narrow point spread function, detective quantum efficiency ≥ 0.8 even without single electron arrival discrimination, and it is resilient to radiation damage.

Ferroelectricity in Si-Doped Hafnia: Probing Challenges in Absence of Screening Charges.

The ability to develop ferroelectric materials using binary oxides is critical to enable novel low-power, high-density non-volatile memory and fast switching logic. The discovery of ferroelectricity in hafnia-based thin films, has focused the hopes of the community on this class of materials to overcome the existing problems of perovskite-based integrated ferroelectrics. However, both the control of ferroelectricity in doped-HfO and the direct characterization at the nanoscale of ferroelectric phenomena, are increasingly difficult to achieve.

The flexoelectric effect in Al-doped hafnium oxide.

After the successful introduction as a replacement for the SiO2 gate dielectric in metal-oxide-semiconductor field-effect transistors, HfO2 is currently one of the most studied binary oxide systems with ubiquitous applications in nanoelectronics. For years, the interest of microelectronic downscaling has focused on tuning the dielectric constant of HfO2, particularly for monoclinic and tetragonal phases. Recently, Müller et al.

Phase equilibria and transition mechanisms in high-pressure AgCl by ab initio methods.

The theoretical study of pressure-driven phase transformations by means of ab initio quantum mechanical methods, in the frame of the extended Landau approach, is considered. A specific application to AgCl is presented: the system shows, on increasing pressure, four polymorphs with rock salt- (Fmm), KOH- (P2(1)/m), TlI- (Cmcm), and CsCl- (Pmm) type structures. The method of constant-pressure enthalpy minimization was used for all phases, by fully relaxing the corresponding crystal structures.