Non-destructive Readout Capability Research Articles

Achieving Single-Electron Sensitivity at Enhanced Speed in Fully Depleted CCDs with Double-Gate MOSFETs.

We introduce a new output amplifier for fully depleted thick p-channel CCDs based on double-gate MOSFETs. The charge amplifier is an n-type MOSFET specifically designed and operated to couple the fully depleted CCD with high charge-transfer efficiency. The junction coupling between the CCD and MOSFET channels has enabled high sensitivity, demonstrating readout noise of 0.74 e_{rms}^{-}/pix in one pixel charge measurement. We have also demonstrated the nondestructive readout capability of the device. Single-electron and single-photon per pixel counting in the entire CCD pixel array has been made possible through the averaging of ten samples, achieving 0.15 e_{rms}^{-}/pix in a pixel readout time of 2.74ms. We have demonstrated fully depleted CCD readout with better performance than the floating diffusion and floating gate amplifiers available today, in both single and multisampling regimes, boasting at least 6 times the speed of floating gate amplifiers.

Non-volatile optical memory based on cooperative orientation switching: improvement of recording speed and contrast by utilizing out-of-plane orientation mode.

Herein, we report a novel strategy toward non-volatile optical memory with high-contrast, high-speed recording, and non-destructive readout capability based on the cooperative out-of-plane orientation of a fluorescent dye doped into azobenzene liquid crystalline polymer film. By employing the out-of-plane orientation switching upon irradiation with UV light and thermal heating, high-contrast turn-on fluorescence switching was successfully achieved and the optical recording was demonstrated with non-destructive fluorescence readout capability. Furthermore, the recording speed and the fluorescence on/off contrast in the present system were dramatically improved compared to the previous in-plane orientation mode.

An orthogonal photoresponsive tristable [3]rotaxane with non-destructive readout

An orthogonal photoresponsive [3]rotaxane is constructed by introducing two orthogonal photoswitchable azobenzene binding sites, and it features reversible photoregulated tristate absorption spectral changes with non-destructive readout capability.

Carbon nanotube ferroelectric random access memory cell based on omega-shaped ferroelectric gate

This paper presents a flexible ferroelectric random access memory (FeRAM) cell with a one-transistor-one-transistor structure. The FeRAM cell was composed of a control transistor (CT) and an omega-shaped ferroelectric memory transistor (MT). An inkjet-printed single-walled carbon nanotube (SWCNT) were utilized as a semiconducting channel layers of both transistors. An omega-shaped ferroelectric gate was formed through inkjet-printing of poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) onto the SWCNT channel of the MT. The gate electrode of the CT was electrically connected to the drain electrode of the MT, while the gate electrode of the MT was connected to the source electrode of the CT. The 1T1T architecture enabled the separation of the writing and reading operations, which afforded nondestructive readout capability. The desired multi-level conductance states could be deterministically controlled by tuning the dipole polarization in the ferroelectric P(VDF-TrFE) layer of the MT. The resulting FeRAM cell showed excellent device performances such as five-level data storage, a high programming/erasing current ratio (>105), a retention time (>104 s), and operational stability (>1000 cycles). The 1T1T FeRAM cell fabricated by inkjet printing technique opens up new opportunities for realizing future large-area flexible memory cells.

Combining research with safety: Performance of the Wendelstein 7-X video diagnostic system

A multi-purpose overview video system, based on EDICAM cameras, was set up at Wendelstein 7-X stellarator, in order to fulfill both machine protection and scientific observation purposes. Places of strong plasma-wall interaction, which can easily evolve to hot-spots, were detected by the EDICAM operators during plasma operation, based on intense local light emission. The EDICAM system was successfully used to avoid hot-spot formation during the commissioning of magnetic configurations with plasma operation. Featuring non-destructive readout capability, smaller areas of the torus interior could be monitored ca. two orders of magnitude faster, in parallel to the normal full frame overview. These fast measurements could be used to show the presence of plasma turbulence (filaments), also detected by other diagnostic systems.

Reversible upconversion switching for Ho/Yb codoped (K,Na)NbO3 ceramics with excellent luminescence readout capability

AbstractLuminescent readout capability for photochromic materials plays a critical role in 3D optical data storage applications, especially for inorganic photochromic materials in the solid‐state form. In our previous studies, we found that the luminescent readout capability can be improved using two or multiple‐photon excited luminescent mode (upconversion), which can effectively decrease the destruction degree of the excitation energies to the stored information during the luminescent “reading” process. However, the luminescent readout performance is unsatisfactory owing to the absence of nondestructive luminescence readout capability. Herein, we report a new solid‐state photochromic material with excellent upconversion readout capability: Ho3+/Yb3+ codoped (K,Na)NbO3. Upon 407 nm light irradiation, the luminescent switching contrast (ΔRt) is up to 78%. Particularly, the materials almost have no any re‐absorption to 980 nm light, exhibiting extremely low destruction to information recording points. The luminescent readout intensity retains 96% after constant 980 nm irradiation for 4 minutes at a high pumping power of 1W, which is superior to our previously reported results (Er/Yb codoped Bi2.5Na0.5Nb2O9 materials). This work would help to further develop new inorganic photochromic materials with high performance to satisfy the requirements for optical storage devices.

Low-voltage-driven Pt/BiFeO3/DyScO3/p-Si-based metal–ferroelectric–insulator–semiconductor device for non-volatile memory

In recent years, ferroelectric random access memory has drawn considerable attention as promising replacement to both dynamic random access memory and flash memory. Specifically in metal–ferroelectric–insulator–semiconductor (MFIS)-based structures, bi-stable polarization of ferroelectric gate even in absence of power holds the resistance state of semiconductor-drain channel between two logic states and offers additional features of non-destructive readout and non-volatile storage capability. However, insulating layer in such structure leads to high depolarizing field across FE layer and in turn high-voltage operation. In the present work, comprehensive performance of low-voltage-driven MFIS device, i.e., Pt (40 nm)/BiFeO3 (265 nm)/DyScO3 (6 nm)/Si is evaluated for gate voltage stress (± 2 to ± 9 V) at different thermal agitation (200–400 K). Fat capacitance–voltage (C–V) hysteresis centered at zero bias with large memory window (ΔV FB) of 1.9 V at low operating voltage of ± 5 V, and stable data retention with distinguishable ON/OFF state values specifies strong charge storage potential of MFIS device in extreme conditions of ± 100 K. X-ray diffraction revealed polycrystalline and rhombohedral R3c phase of BiFeO3 film and out-of-plane piezoresponse force microscopy analysis showed the ultrafast domain switching with sharp contrast. Complete 180° phase reversal in hysteresis loop and bufferfly-shaped piezo-actuation amplitude loop further confirmed the enhanced ferroelectric properties of BiFeO3 thin films. Nonlinear J–V curves of MFIS structure were investigated to understand the device reliability and charge transport mechanism. These encouraging results are crucial for designing more reliable integrated MFIS-based non-destructive readout non-volatile memory devices.

High-Performance Polymer Semiconductor-Based Nonvolatile Memory Cells with Nondestructive Read-Out

In this manuscript, the fabrication of polymer nonvolatile memory cells based on one-transistor–one-transistor (1T1T) device geometries is reported. A spin-coated diketopyrrolopyrrole (DPP)-based polymer semiconductor was used as the active channel layer for both the control transistor (CT) and memory transistor (MT); thermally deposited gold nanoparticles (Au NPs) were inserted between the tunneling and blocking gate dielectrics as a charge-trapping layer of the MT. In the 1T1T memory cell, the source electrode of the CT was connected to the gate electrode of the MT, while the drain electrode of the MT was connected to the gate electrode of the CT. The reading and writing processes of the memory cells operated separately, which yielded a nondestructive read-out capability. The fabricated 1T1T polymer memory cells exhibited excellent device performances with a large memory window of 16.1 V, a high programming–erasing current ratio >103, a long retention of 103 s, a cyclic stability of 500 cycles, and a 2-...

Halogen-bridged metal-organic frameworks constructed from bipyridinium-based ligand: structures, photochromism and non-destructive readout luminescence switching.

Two isomorphous halogen-bridged metal-organic frameworks have been solvothermally synthesized based on the bipyridinium ligand and structurally characterized. The two compounds show an eye-detectable color development upon light irradiation, but different coloration degrees. The relationship between the structure and photosensitivity has been studied in detail. The photochromic properties of the bipyridinium unit have been used to modulate the luminescence under light illumination. Compound 1 is the first example showing photo-modulated luminescence switching featuring a non-destructive readout capability based on transition metals.

Phenanthrene-bridged diarylethenes: Synthesis, photochromism and non-destructive readout

Abstract Here we report on the synthesis and photochromism of a group of newly designed phenanthrene-bridged diarylethenes. The structure of one diarylethene derivative was determined by single crystal X-ray diffraction analysis. The photochromic dyes cyclize smoothly in polar organic solvents and water upon UV light irradiation while undergo fading under visible light. These photochromic materials have non-destructive readout capability through fluorescent modulation. Fluorescent read-out lights of them are 390 and 385 nm respectively. The non-destructive read out capability of them was studied with density functional theory and the results indicated that the cyclization probably took place at the second rather than the first excited states.

A luminescent steroid-based organogel: ON–OFF photoswitching by dopant interplay and templated synthesis of fluorescent nanoparticles

The modulation of the fluorescence emission of a perylene dye between ON and OFF states was achieved with high efficiency by means of a diarylethene photochromic compound in an organogel medium. Fluorescent gels were prepared from a steroidal low molecular weight organogelator doped with the perylene fluorophore. The compatibility of the photochromic compound in this medium and the non-destructive readout capability were demonstrated. The dye doped organogel was further used as a template and an innovative method was employed to grow fluorescent silica spherical nanoparticles with physically and chemically admixed perylene dye.

Single-Molecule Fluorescence Photoswitching of a Diarylethene−Perylenebisimide Dyad: Non-destructive Fluorescence Readout

Single-molecule fluorescence photoswitching plays an essential role in ultrahigh-density (Tbits/inch(2)) optical memories and super-high-resolution fluorescence imaging. Although several fluorescent photochromic molecules and fluorescent proteins have been applied, so far, to optical memories and super-high-resolution imaging, their performance is unsatisfactory because of the absence of "non-destructive fluorescence readout capability". Here we report on a new molecular design principle of a molecule having non-destructive readout capability. The molecule is composed of acceptor photochromic diarylethene and donor fluorescent perylenebisimide units. The fluorescence is reversibly quenched when the diarylethene unit converts between the open- and the closed-ring isomers upon irradiation with visible and UV light. The fluorescence quenching is based on an electron transfer from the donor to the acceptor units. The fluorescence photoswitching and non-destructive readout capability were demonstrated in solution (an ensemble state) and at the single-molecule level. Femtosecond time-resolved transient and fluorescent lifetime measurements confirmed that the fluorescence quenching is attributed to the intramolecular electron transfer.

Printed Nonvolatile Memory for a Sheet-Type Communication System

By using state-of-the-art printing technologies and functional inks, we have demonstrated organic nonvolatile flexible random-access-memory matrices with a nondestructive read-out capability and a time-continuous current output; these functionalities have not been simultaneously achieved even by silicon-based conventional memory. A memory cell comprising three transistors becomes possible with inkjet printing and other solution-based processes, which can use ferroelectric copolymer ink comprising poly(vinylidenefluoride-co-trifluoroethylene) and insulating ink comprising polyimide precursors properly within the planer plastic substrate. A large ldquo1 : 0rdquo current ratio of 105 is observed in air when it is annealed at 135degC , which is sufficiently low to be compatible with many plastic substrates. When stored in air, the ldquo1 : 0rdquo ratio was still 104 after 15 days and 103 after 5 months, which is sufficient for practical applications. Furthermore, human-scale communication sheets were manufactured as the first demonstration utilizing large-area organic memories.

Up-conversion luminescent switch based on photochromic diarylethene and rare-earth nanophosphors

We have demonstrated a novel and unique route to a highly efficient luminescent switch with nondestructive readout capability by utilizing photochromic diarylethene and up-conversion LaF(3):Yb,Ho nanophosphors.

Read-Noise Characterization of Focal Plane Array Detectors via Mean-Variance Analysis

Mean-variance analysis is described as a method for characterization of the read-noise and gain of focal plane array (FPA) detectors, including charge-coupled devices (CCDs), charge-injection devices (CIDs), and complementary metal-oxide-semiconductor (CMOS) multiplexers (infrared arrays). Practical FPA detector characterization is outlined. The nondestructive readout capability available in some CIDs and FPA devices is discussed as a means for signal-to-noise ratio improvement. Derivations of the equations are fully presented to unify understanding of this method by the spectroscopic community.

New photochromic copolymers with bisthienylethene pendant groups

The reactivity of photochromic polymer is required to be improved, and the concentration of photochrome dispersed in polymer matrices is generally limited. New copolymers having photochromic unit as pendant groups are still required to be developed. Here we report two new copolymers, which are expected to have two advantages: the concentration of photochromic bisthienylethene is high enough for the use in optical memory media. The photochromic reactivity of the copolymer below and above Tg is different, which is useful for non-destructive readout capability.

Signal-to-noise ratio of nondestructive photocurrent-detection readout in near-field photochromic memory: theoretical study

The signal-to-noise ratio (SNR) and possible data-transfer rate of nondestructive photocurrent-detection readout in near-field photochromic memory were calculated theoretically. The photocurrent-detection readout provided a much higher SNR and a higher data-transfer rate than those of conventional transmittance-detection readout. The SNR of the photocurrent-detection readout was dependent on the electric field applied to the medium and the potential barrier height between the photochromic recording layer and the photoabsorbing layer. A sufficient SNR was obtained under the conditions of an electric field of 2.5 V/m and a potential barrier height <0.4 eV in land area. Photocurrent-detection readout is a promising method to achieve high SNR, high data-transfer rate, and ultrahigh recording density with nondestructive-readout capability.

A Stacked CMOS Active Pixel Image Sensor for Charge Particle Detection and the Application to SIMS

A stacked CMOS active pixel image-sensor (APS) has been developed for detecting various kinds of charged particles and its noise performance has been measured and analyzed. The sensitivity for ions and electrons with keV energy level utilizes for ion microscopy such-as SIMS and electron microscopy, respectively.Charge particles such as ions and electrons with kinetic energy of keV order are useful probes for surface analysis of material. A measurement system which yields two-dimensional image of charge particles is highly demanded. The conventional two-dimensional detection system is composed of a micro channel plate, a florescent plate which receives multiplied secondary electrons and generates a visible image, and a visible image sensor. However, its limited dynamic range and non-linearity in the ion-electron-to-photon conversion process make a quantitative measurement difficult. The proposed system using a stacked CMOS APS has several advantages over the conventional system such as high spatial resolution, no insensitive time, high S/N, wide dynamic range, nondestructive readout capability, high robustness, and low power consumption.

The Direct Ion Storage Dosemeter

The direct ion storage (DIS) dosemeter is based on the combination of an ion chamber and a non-volatile electronic charge storage element. This allows a new type passive dosemeter to be constructed with dosimetric characteristics ideally suited for measuring the H p (10 and H p (0.07) operational quantities. The DIS dosemeter is a passive device by nature but a direct nondestructive readout capability allows it to be used also as the detecting element in a personal alarming dosemeter. The features and benefits of an electronic legal dosemeter (ELD) system are described and the operational characteristics and specifications are presented and compared with conventional solid state and electronic dosimetry systems.

Analytical model in a weakly coupled sandwich for memory purposes

A simple analytical model explains giant magnetoresistive properties in a weakly coupled sandwich with two magnetic components. The model describes in detail a new storage mechanism in which the minor loop’s slope depends on its past magnetic histories. A new type of solid-state giant magnetoresistance memory based upon this mechanism has been realized by experiments. Furthermore, some important factors included in nondestructive readout capability are also analyzed by this model.