Advances in Conceptual Electronic Nanodevices based on 0D and 1D Nanomaterials

Nanoelectronic devices are being extensively developed in these years with a large variety of potential applications. In this article, some recent developments in nanoelectronic devices, including their principles, structures and potential applications are reviewed. As nanodevices work in nanometer dimensions, they consume much less power and function much faster than conventional microelectronic devices. Nanoelectronic devices can operate in different principles so that they can be further grouped into field emission devices,molecular devices, quantum devices, etc. Nanodevices can function as sensors, diodes, transistors, photovoltaic and light emitting devices, etc. Recent advances in both theoretical simulation and fabrication technologies expedite the development process from device design to prototype demonstration. Practical applications with a great market value from nanoelectronic devices are expected in near future.

Low Power Computing Paradigms Based on Emerging Non-Volatile Nanodevices

Traditional digital processing approaches are based on semiconductor transistors, which suffer from high power consumption, aggravating with technology node scaling. To solve definitively this problem, a number of emerging non-volatile nanodevices are under intense investigations. Meanwhile, novel computing circuits are invented to dig the full potential of the nanodevices. The combination of non-volatile nanodevices with suitable computing paradigms have many merits compared with the complementary metal-oxide-semiconductor transistor （CMOS） technology based structures, such as zero standby power, ultra-high density, non-volatility, and acceptable access speed. In this paper, we overview and compare the computing paradigms based on the emerging nanodevices towards ultra-low dissipation.

Fano Factor in Strained Graphene Nanoribbon Nanodevices

We investigate the Fano factor in a strained armchair and zigzag graphene nanoribbon nanodevice under the effect of ac field in a wide range of frequencies at different temperatures （10？K–70？K）. This nanodevice is modeled as follows： a graphene nanoribbon is connected to two metallic leads. These two metallic leads operate as a source and a drain. The conducting substance is the gate electrode in this three-terminal nanodevice. Another metallic gate is used to govern the electrostatics and the switching of the graphene nanoribbon channel. The substances at the graphene nanoribbon/metal contact are controlled by the back gate. The photon-assisted tunneling probability is deduced by solving the Dirac eigenvalue differential equation in which the Fano factor is expressed in terms of this tunneling probability. The results show that for the investigated nanodevice, the Fano factor decreases as the frequency of the induced ac field increases, while it increases as the temperature increases. In general, the Fano factors for both strained armchair and zigzag graphene nanoribbons are different. This is due to the effect of the uniaxial strain. It is shown that the band structure parameters of graphene nanoribbons at the energy gap, the C–C bond length, the hopping integral, the Fermi energy and the width are modulated by uniaxial strain. This research gives us a promise of the present nanodevice being used for digital nanoelectronics and sensors.

On a Predictive Scheme of Slow Photoconductive Gain Evolution in Epitaxial Layer/Substrate Optoelectronic Nanodevices

The photoconductive response of the fundamental type of diodic nanodevice comprising a low resistivity, n-type epitaxial layer and a semi-insulating substrate is considered in terms of the optoelectronic parameter of photoconductive gain as experimentally measurable through monitoring the temporal evolution of conductivity current photoenhancement under continuous epilayer illumination-exposure. A modelling taking into account the built-in potential barrier of the interface of the epitaxial layer/substrate device (ESD) as well as its modification by the photovoltage induced within the illuminated ESD diode leads to predicting the technologically exploitable possibility of a notably slow photonic dose-evolution (exposure time-development) of the optonanoelectronics ESD photoconductive gain.

Monitoring of Cell Membrane Microenvironment Based on DNA Nanodevices

The cell membrane is a critical barrier for cellular homeostasis,integral to signaling and intercellular communication,and vital for understanding cellular functions and disease mechanisms.Investigating its microenvironment is crucial for uncovering the molecular basis of physiological and pathological processes associated with the cell membrane,driving the development of bioanalytical toolkits capable of dynamically monitoring the cell surface microenvironment.With the continuous advancement of functional nucleic acids and dynamic DNA nanotechnology,DNA nanodevices with controllable nanosized geometry,specific molecular recognition,and selective membrane-localization properties offer a versatile platform for probing the cell membrane microenvironment.In this review,we summarize the current biosensing and membrane-anchoring mechanisms of DNA nanodevices and highlight their use in studying key cell membrane events,including membrane lipid dynamics,transmembrane transport,receptor dimerization,and signal transduction.Furthermore,we discuss the challenges and potential future applications of DNA nanodevices in advancing cell membrane biology research and biomedical applications.

Construction and Application of DNAzyme-based Nanodevices

The development of stimuli-responsive nanodevices with high efficiency and specificity is very important in biosensing,drug delivery,and so on.DNAzymes are a class of DNA molecules with the specific catalytic activity.Owing to their unique catalytic activity and easy design and synthesis,the construction and application of DNAzymes-based nanodevices have attracted much attention in recent years.In this review,the classification and properties of DNAzyme are first introduced.The construction of several common kinds of DNAzyme-based nanodevices,such as DNA motors,signal amplifiers,and logic gates,is then systematically summarized.We also introduce the application of DNAzyme-based nanodevices in sensing and therapeutic fields.In addition,current limitations and future directions are discussed.

Efficient design method for cell allocation in hybrid CMOS/nanodevices using a cultural algorithm with chaotic behavior

The hybrid CMOS molecular （CMOL） circuit, which combines complementary metal-oxide- semiconductor （CMOS） components with nanoscale wires and switches, can exhibit significantly improved performance. In CMOL circuits, the nanodevices, which are called cells, should be placed appropriately and are connected by nanowires. The cells should be connected such that they follow the shortest path. This paper presents an efficient method of cell allocation in CMOL circuits with the hybrid CMOS/nanodevice structure; the method is based on a cultural algorithm with chaotic behavior. The optimal model of cell allocation is derived, and the coding of an individual represent- ing a cell allocation is described. Then the cultural algorithm with chaotic behavior is designed to solve the optimal model. The cultural algorithm consists of a population space, a belief space, and a protocol that describes how knowledge is exchanged between the population and belief spaces. In this paper, the evolutionary processes of the population space employ a genetic algorithm in which three populations undergo parallel evolution. The evolutionary processes of the belief space use a chaotic ant colony algorithm. Extensive experiments on cell allocation in benchmark circuits showed that a low area usage can be obtained using the proposed method, and the computation time can be reduced greatly compared to that of a conventional genetic algorithm.

Semi-custom methodology to fabricate transmission electron microscopy chip for in situ characterization of nanodevices and nanomaterials

The fabrication of nanodevices on the delicate membrane window of the TEM(transmission electron microscopy)chip has the risk of breakage failure,limiting in-depth research in this area.This work proposed a methodology to address this issue,enabling secure in-situ transmission electron microscopic observation of many devices and materials that would otherwise be difficult to achieve.Combining semi-custom TEM chip design and front-side protected release technology,a variety of nanodevices were successfully fabricated onto the window membrane of the TEM chip and studied in situ.Moreover,the pressure tolerance of window membrane was investigated and enhanced with a reinforcing structure.As an example of typical applications,MoS;devices on the TEM chip have been fabricated and electron beam-induced gate modulation and irradiation damage effects,have been demonstrated.

Recent Advances in Directed Assembly of Nanowires or Nanotubes

Nanowires and nanotubes of diverse material compositions,properties and/or functions have been produced or fabricated through various bottom-up or top-down approaches.These nanowires or nanotubes have also been utilized as potential building blocks for functional nanodevices.The key for the integration of those nanowire or nanotube based devices is to assemble these one dimensional nanomaterials to specific locations using techniques that are highly controllable and scalable.Ideally such techniques should enable assembly of highly uniform nanowire/nanotube arrays with precise control of density,location,dimension or even material types of nanowires/nanotubes.Numerous assembly techniques are being developed that can quickly align and assemble large quantities of one type or multiple types of nanowires through parallel processes,including flow-assisted alignment,Langmuir-Blodgett assembly,bubble-blown technique,electric/magnetic-field directed assembly,contact/roll printing,knocking-down,etc..With these assembling techniques,applications of nanowire/nanotube based devices such as flexible electronics and sensors have been demonstrated.This paper delivers an overall review of directed nanowire/nanotube assembling approaches and analyzes advantages and limitations of each method.The future research directions have also been discussed.

One-dimensional ZnS-based Hetero-,Core/shell and Hierarchical Nanostructures

A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional （1D） ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications.

Nanotechnology in diagnosis and therapy of gastrointestinal cancer

Advances in nanotechnology have opened new frontiers in the diagnosis and treatment of cancer.Nanoparticle-based technology improves the precision of tumor diagnosis when combined with imaging,as well as the accuracy of drug target delivery,with fewer side effects.Optimized nanosystems have demonstrated advantages in many fields,including enhanced specificity of detection,reduced toxicity of drugs,enhanced effect of contrast agents,and advanced diagnosis and therapy of gastrointestinal(GI)cancers.In this review,we summarize the current nanotechnologies in diagnosis and treatment of GI cancers.The development of nanotechnology will lead to personalized approaches for early diagnosis and treatment of GI cancers.

Plasmons in a free-standing nanorod with a two-dimensional parabolic quantum well caused by surface states

The collective charge density excitations in a free-standing nanorod with a two-dimensional parabolic quantum well are investigated within the framework of Bohm-Pine＇s random-phase approximation in the two-subband model.The new simplified analytical expressions of the Coulomb interaction matrix elements and dielectric functions are derived and numerically discussed.In addition,the electron density and temperature dependences of dispersion features are also investigated.We find that in the two-dimensional parabolic quantum well,the intrasubband upper branch is coupled with the intersubband mode,which is quite different from other quasi-one-dimensional systems like a cylindrical quantum wire with an infinite rectangular potential.In addition,we also find that higher temperature results in the intersubband mode（with an energy of 12 meV（～ 3 THz）） becoming totally damped,which agrees well with the experimental results of Raman scattering in the literature.These interesting properties may provide useful references to the design of free-standing nanorod based devices.

Hybrid femtosecond laser three-dimensional micro-and nanoprocessing:a review

The extremely high peak intensity associated with ultrashort pulse width of femtosecond(fs)lasers enabled inducing nonlinear multiphoton absorption in materials that are transparent to the laser wavelength.More importantly,focusing the fs laser beam inside the transparent materials confined the nonlinear interaction to within the focal volume only,realizing three-dimensional(3D)micro/nanofabrication.This 3D capability offers three different processing schemes for use in fabrication:undeformative,subtractive,and additive.Furthermore,a hybrid approach of different schemes can create much more complex 3D structures and thereby promises to enhance the functionality of the structures created.Thus,hybrid fs laser 3D microprocessing opens a new door for material processing.This paper comprehensively reviews different types of hybrid fs laser 3D micro/nanoprocessing for diverse applications including fabrication of functional micro/nanodevices.

Impact of energy straggle on proton-induced single event upset test in a 65-nm SRAM cell

This paper presents a simulation study of the impact of energy straggle on a proton-induced single event upset （SEU） test in a commercial 65-nm static random access memory cell. The simulation results indicate that the SEU cross sections for low energy protons are significantly underestimated due to the use of degraders in the SEU test. In contrast, using degraders in a high energy proton test may cause the overestimation of the SEU cross sections. The results are confirmed by the experimental data and the impact of energy straggle on the SEU cross section needs to be taken into account when conducting a proton-induced SEU test in a nanodevice using degraders.

Recent electroporation-based systems for intracellular molecule delivery

Intracellular delivery of functional molecules,such as DNA probes and plasmids,is an important method for investigating cellular mechanisms and changing cell fates in biomedicine.Among various delivery methods,recent years have seen the emergence of electroporation-based techniques that provide versatile platforms for molecule delivery,with high efficiency and controlled dosage.In this Review,we describe recent electroporation-based systems for intracellular molecule delivery.The principles of electroporation for cell membrane perforation and cargo delivery are briefly summarized.Focusing on various scenarios for the application of electroporation,we review electroporation devices that variously employ structures based on nanochannels,nanostraws,and flow-through microfluidic channels for in vitro intracellular molecule delivery.We also consider in vivo targeted therapies based on delivery of active molecules by electroporation according to the lesion locations.Finally,we discuss the current challenges facing electroporation-based techniques,as well as opportunities for their future development,which may lead to innovations in intracellular molecule delivery both for cellular analysis in the laboratory and treatment in the clinic.

THz Oscillations in a GaN Based Planar Nano-Device

Gunn oscillations in a GaN based planar nano-device have been studied by ensemble Monte Carlo (EMC) method. Simulation results show that when the channel length of the device reduces to 450 nm, THz oscillations (about 0.3 THz) can be obtained. Also the phase of the oscillations can be controlled by the initial conditions that excite the Gunn domains. Moreover, through adjusting the phase difference between the oscillations in a double-channels device, which attained by parallel connecting two single-channel devices, the frequency of the device shifts from 0.3 THz to 0.6 THz. This phenomenon remains in devices with shorter channel-length, unless the channel-length is too short to support Gunn oscillations. The possible underlying mechanisms are also discussed.

A Notional Duette on Nanophotonics Fundamentals

A two-part Notional Synthesis on Nanophotonics Fundamentals is being carried out: On the one hand, a rather novel depiction of the Fermionic Quantum Causality is being attempted. On the other hand, a Nanophotonic Response Encoder is being devised: Illuminated Electrons are the original Protagonists.

Charge qubits based on ultra-thin topological insulator films

We study how to use the surface states in a Bi2Se3 topological insulator ultra-thin film that are affected by finite size effects for the purpose of quantum computing.We demonstrate that:(i)surface states under the finite size effect can effectively form a two-level system where their energy levels lie in between the bulk energy gap and a logic qubit can be constructed,(ii)the qubit can be initialized and manipulated using electric pulses of simple forms,(iii)two-qubit entanglement is achieved through a√SWAP operation when the two qubits are in a parallel setup,and(iv)alternatively,a Floquet state can be exploited to construct a qubit and two Floquet qubits can be entangled through a Controlled-NOT operation.The Floquet qubit offers robustness to background noise since there is always an oscillating electric field applied,and the single qubit operations are controlled by amplitude modulation of the oscillating field,which is convenient experimentally.

An aptamer-driven DNA nanodevice for improved delivery of synthetic immunostimulants

Efficient delivery of therapeutics to immune cells remains a formidable challenge for cancer immunotherapy.In this work,we demonstrate that an aptamer-driven DNA nanodevice,constructed through linkage of a synthetic immunostimulant(Toll-like receptor 9 agonist:CpG motif)to an aptamer,could significantly enhance the immunostimulatory activity by facilitating the uptake and retention of therapeutics in macrophages.Systemic administration of the DNA nanodevice results in efficient tumor growth inhibition in both breast cancer and melanoma mouse models.Our studies suggest that the DNA nanodevice leads to reeducation of tumor-associated macrophages and ultimately to reversing the tumor immune microenvironment.The strategy for aptamer-mediated and vehicle-free delivery of immunostimulatory oligonucleotides provides a potential platform for cancer immunotherapy.

An AND-Gate DNA Nanodevice for Dual Protein-Mediated,Tumor-Specific Imaging

Sensitive and specific imaging of tumor-associated biomarkers offers an effective way for cancer diagnosis.However,most of the reported imaging probes are limited to the targeting of a single biomarker,which may impair imaging precision.Here,we report an aptamer-based,AND-gate DNA nanodevice that relies on the sequential processing of two tumor-associated proteins to produce a specific fluorescent signal for precise tumor imaging.The DNA nanodevice integrates an AS1411 aptamer to bind cell surface nucleolin for tumor targeting and a DNA sensor to respond to intracellular apurinic/apyrimidinic endonuclease 1 for activatable imaging.We evaluated the performance of the system in both living cells and a tumor-bearing mouse model,and demonstrated its capability in tumor cell-specific imaging.We anticipate that this strategy will accelerate the design of multivariate protein-stimulated probes for tumor diagnosis.