ترغب بنشر مسار تعليمي؟ اضغط هنا

GHz Operation of Nanometer-Scale Metallic Memristors: Highly Transparent Conductance Channels in Ag$_{2}$S Devices

129   0   0.0 ( 0 )
 نشر من قبل Mikl\\'os Csontos Dr.
 تاريخ النشر 2013
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

The nonlinear transport properties of nanometer-scale junctions formed between an inert metallic tip and an Ag film covered by a thin Ag$_{2}$S layer are investigated. Suitably prepared samples exhibit memristive behavior with technologically optimal ON and OFF state resistances yielding to resistive switching on the nanosecond time scale. Utilizing point contact Andreev reflection spectroscopy we studied the nature of electron transport in the active volume of the memristive junctions showing that both the ON and OFF states correspond to truly nanometer scale, highly transparent metallic channels. Our results demonstrate the merits of Ag$_{2}$S nanojunctions as nanometer-scale memory cells with GHz operation frequencies.

قيم البحث

اقرأ أيضاً

Prevailing models of resistive switching arising from electrochemical formation of conducting filaments across solid state ionic conductors commonly attribute the observed polarity of the voltage-biased switching to the sequence of the active and ine rt electrodes confining the resistive switching memory cell. Here we demonstrate equivalent, stable switching behavior in metallic Ag-Ag$_{2}$S-Ag nanojunctions at room temperature. Our experimental results and numerical simulations reveal that the polarity of the switchings is solely determined by the geometrical asymmetry of the electrode surfaces. By the lithographical design of a proof of principle device we demonstrate the merits of simplified fabrication of atomic-scale, robust planar Ag$_{2}$S memory cells.
In this work, we evaluate a multitude of metal-oxide bi-layers and demonstrate the benefits from increased memory stability via multibit memory operation. We introduce a programming methodology that allows for operating metal-oxide memristive devices as multibit memory elements with highly packed yet clearly discernible memory states. We finally demonstrate a 5.5-bit memory cell (47 resistive states) with excellent retention and power consumption performance. This paves the way for neuromorphic and non-volatile memory applications.
Integrating nano-scale objects, such as single molecules or carbon nanotubes, into impedance transformers and performing radio-frequency measurements allows for high time-resolution transport measurements with improved signal-to-noise ratios. The rea lization of such transformers implemented with superconducting transmission lines for the 2-10 GHz frequency range is presented here. Controlled electromigration of an integrated gold break junction is used to characterize a 6 GHz impedance matching device. The real part of the RF impedance of the break junction extracted from microwave reflectometry at a maximum bandwidth of 45 MHz of the matching circuit is in good agreement with the measured direct current resistance.
71 - Wei Ren , C. T. Chan , T. H. Cho 2008
We report a first principles analysis of electronic transport characteristics for (n,n) carbon nanotube bundles. When n is not a multiple of 3, inter-tube coupling causes universal conductance suppression near Fermi level regardless of the rotational arrangement of individual tubes. However, when n is a multiple of 3, the bundles exhibit a diversified conductance dependence on the orientation details of the constituent tubes. The total energy of the bundle is also sensitive to the orientation arrangement only when n is a multiple of 3. All the transport properties and band structures can be well understood from the symmetry consideration of whether the rotational symmetry of the individual tubes is commensurate with that of the bundle.
Self-assembled semiconductor quantum dots show remarkable optical and spin coherence properties, which have lead to a concerted research effort examining their potential as a quantum bit for quantum information science1-6. Here, we present an alterna tive application for such devices, exploiting recent achievements of charge occupation control and the spectral tunability of the optical emission of quantum dots by electric fields7 to demonstrate high-sensitivity electric field measurement. In contrast to existing nanometer-scale electric field sensors, such as single electron transistors8-11 and mechanical resonators12,13, our approach relies on homodyning light resonantly Rayleigh scattered from a quantum dot transition with the excitation laser and phase sensitive lock-in detection. This offers both static and transient field detection ability with high bandwidth operation and near unity quantum efficiency. Our theoretical estimation of the static field sensitivity for typical parameters, 0.5 V/m/ surd Hz, compares favorably to the theoretical limit for single electron transistor-based electrometers. The sensitivity level of 5 V/m/ surd Hz we report in this work, which corresponds to 6.4 * 10-6 e/ surd Hz at a distance of 12 nm, is worse than this theoretical estimate, yet higher than any other result attained at 4.2 K or higher operation temperature.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا