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Articles 511 - 538 of 538
Full-Text Articles in Engineering
Outperforming The Conventional Scaling Rules In The Quantum-Capacitance Limit, Joachim Knoch, W Riess, Joerg Appenzeller
Outperforming The Conventional Scaling Rules In The Quantum-Capacitance Limit, Joachim Knoch, W Riess, Joerg Appenzeller
Other Nanotechnology Publications
We present a study on the scaling behavior of field-effect transistors in the quantum-capacitance limit (QCL). It will be shown that a significant performance improvement in terms of the power delay product can be obtained in devices scaled toward the QCL. As a result, nanowires or nanotubes exhibiting a 1-D transport are a premier choice as active channel materials for transistor devices since the QCL can be attained in such systems.
Determination Of The Eigenstates And Wavefunctions Of A Single Gated As Donor, Gabriel P. Lansbergen, R. Rahman, C. J. Wellard, P. E. Rutten, J. Caro, I. Woo, N. Colleart, S. Biersemans, Gerhard Klimeck
Determination Of The Eigenstates And Wavefunctions Of A Single Gated As Donor, Gabriel P. Lansbergen, R. Rahman, C. J. Wellard, P. E. Rutten, J. Caro, I. Woo, N. Colleart, S. Biersemans, Gerhard Klimeck
Other Nanotechnology Publications
Current semiconductor devices have been scaled to such dimensions that we need take atomistic approach to understand their operation for nano-electronics. From a bottomsup perspective, the smallest functional element within a nanodevice would be a single (dopant) atom itself. Control and understanding over the eigenenergies and wavefunctions of a single dopant could prove a key ingredient for device technology beyond-CMOS. Here, we will discuss the eigenlevels of a single As donor in a three terminal configuration. The donor is incorporated in the channel of prototype transistors called FinFETs. The measured eigenlevels are shown to consist of levels associated with the …
Nanopatterning Using Nsom Probes Integrated With High Transmission Nanoscale Bowtie Aperture, Nicholas Murphy-Dubay, Liang Wang, Edward C. Kinzel, Sreemanth Mv Uppuluri, Xianfan Xu
Nanopatterning Using Nsom Probes Integrated With High Transmission Nanoscale Bowtie Aperture, Nicholas Murphy-Dubay, Liang Wang, Edward C. Kinzel, Sreemanth Mv Uppuluri, Xianfan Xu
Birck and NCN Publications
Nanoscale ridge aperture antennas have been shown to have high transmission efficiency and confined nanoscale radiation in the near field region compared with regularly-shaped apertures. The radiation enhancement is attributed to the fundamental electric-magnetic field propagating in the TE10 mode concentrated in the gap between the ridges. This paper reports experimental demonstration of field enhancement using such ridge antenna apertures in a bowtie shape for the manufacture of nanometer size structures using an NSOM (near field scanning optical microscopy) probe integrated with nanoscale bowtie aperture. Consistent lines with width of 59 nm and as small as 24 nm have be …
Externally Assembled Gate-All-Around Carbon Nanotube Field-Effect Transistor, Zhihong Chen, Damon Farmer, Sheng Xu, Roy Gordon, Phaedon Avouris, Joerg Appenzeller
Externally Assembled Gate-All-Around Carbon Nanotube Field-Effect Transistor, Zhihong Chen, Damon Farmer, Sheng Xu, Roy Gordon, Phaedon Avouris, Joerg Appenzeller
Other Nanotechnology Publications
In this letter, we demonstrate a gate-all-around single-wall carbon nanotube field-effect transistor. This is the first successful experimental implementation of an off-chip gate and gate-dielectric assembly with subsequent deposition on a suitable substrate. The fabrication process and device measurements are discussed in the letter. We also argue in how far charges in the gate oxide are responsible for the observed nonideal device performance.
Carbon Nanotubes For High-Performance Electronics - Progress And Prospect, Joerg Appenzeller
Carbon Nanotubes For High-Performance Electronics - Progress And Prospect, Joerg Appenzeller
Other Nanotechnology Publications
Carbon nanotube devices offer intrinsic advantages for high-performance logic device applications. The ultrasmall body of a carbon nanotube-the tube diameter-is the key feature that should allow aggressive channel length scaling, while the intrinsic transport properties of the nanotube ensure at the same time high on-currents. in addition, the narrowness of the tube is critical to implementation of novel device concepts like the tunneling transistor. By understanding the unique capabilities of carbon nanotubes and using them in unconventional designs, novel nanoelectronic applications may become feasible. However, much better control of materials quality must be obtained, and new fabrication processes must be …
Influence Of Phonon Scattering On The Performance Of P-I-N Band-To-Band Tunneling Transistors, Siyuranga O. Koswatta, Mark S. Lundstrom, Dmitri E. Nikonov
Influence Of Phonon Scattering On The Performance Of P-I-N Band-To-Band Tunneling Transistors, Siyuranga O. Koswatta, Mark S. Lundstrom, Dmitri E. Nikonov
Other Nanotechnology Publications
Power dissipation has become a major obstacle in performance scaling of modern integrated circuits and has spurred the search for devices operating at lower voltage swing. In this letter, we study p-i-n band-to-band tunneling field effect transistors taking semiconducting carbon nanotubes as the channel material. The on current of these devices is mainly limited by the tunneling barrier properties, and phonon-scattering has only a moderate effect. We show, however, that the off current is limited by phonon absorption assisted tunneling, and thus is strongly temperature dependent. Subthreshold swings below the 60 mV/decade conventional limit can be readily achieved even at …
Simulation Of Phonon Transport Across A Non-Polar Nanowire Junction Using An Atomistic Green's Function Method, W Zhang, N Mingo, Timothy Fisher
Simulation Of Phonon Transport Across A Non-Polar Nanowire Junction Using An Atomistic Green's Function Method, W Zhang, N Mingo, Timothy Fisher
Birck and NCN Publications
Phonon transport across a non-polar nanowire situated between two semi-infinite contacts is simulated in this paper using the atomistic Green's function method. Abrupt geometric changes between the nanowire and bulk contacts are handled by self-energy matrices obtained from bare surface Green's functions. Transport properties such as phonon transmission functions and thermal conductances are calculated, and their dependencies on the interatomic potential, length, diameter, shape, and lattice orientation are investigated. The results reveal that the overall thermal conductance of the nanowire-bulk-contact structure increases with nanowire diameter while the normalized thermal conductance approaches an asymptotic value. Thermal conductance decreases significantly with increasing …
Gold Nanorods Mediate Tumor Cell Death By Compromising Membrane Integrity, Ling Tong, Yan Zhao, Terry B. Huff, Matthew N. Hansen, Alexander Wei, Ji-Xin Cheng
Gold Nanorods Mediate Tumor Cell Death By Compromising Membrane Integrity, Ling Tong, Yan Zhao, Terry B. Huff, Matthew N. Hansen, Alexander Wei, Ji-Xin Cheng
Other Nanotechnology Publications
Folate-conjugated gold nanorods targeted to tumor cell surfaces produced severe membrane damage upon near-infrared irradiation. Photoinduced injury to the plasma membrane resulted in a rapid increase in intracellular calcium (shown in green) with subsequent disruption of the actin network, featured prominently by the formation of membrane blebs.
In Vivo Quantitation Of Rare Circulating Tumor Cells By Multiphoton Intravital Flow Cytometry, Wei He, Haifeng Wang, Lynn C. Hartmann, Ji-Xin Cheng, Phillip S. Low
In Vivo Quantitation Of Rare Circulating Tumor Cells By Multiphoton Intravital Flow Cytometry, Wei He, Haifeng Wang, Lynn C. Hartmann, Ji-Xin Cheng, Phillip S. Low
Other Nanotechnology Publications
Quantitation of circulating tumor cells (CTCs) constitutes an emerging tool for the diagnosis and staging of cancer, assessment of response to therapy, and evaluation of residual disease after surgery. Unfortunately, no existing technology has the sensitivity to measure the low numbers of tumor cells (< 1 CTC per ml of whole blood) that characterize minimal levels of disease. We present a method, intravital flow cytometry, that noninvasively counts rare CTCs in vivo as they flow through the peripheral vasculature. The method involves i.v. injection of a tumor-specific fluorescent ligand followed by multiphoton fluorescence imaging of superficial blood vessels to quantitate the flowing CTCs. Studies in mice with metastatic tumors demonstrate that CTCs can be quantitated weeks before metastatic disease is detected by other means. Analysis of whole blood samples from cancer patients further establishes that human CTCs can be selectively labeled and quantitated when present at approximate to 2 CTCs per ml, opening opportunities for earlier assessment of metastatic disease.
Brillouin-Zone Unfolding Of Perfect Supercells Having Nonequivalent Primitive Cells Illustrated With A Si/Ge Tight-Binding Parameterization, Timothy B. Boykin, Neerav Kharche, Gerhard Klimeck
Brillouin-Zone Unfolding Of Perfect Supercells Having Nonequivalent Primitive Cells Illustrated With A Si/Ge Tight-Binding Parameterization, Timothy B. Boykin, Neerav Kharche, Gerhard Klimeck
Birck and NCN Publications
Numerical calculations of nanostructure electronic properties are often based on a nonprimitive rectangular unit cell, because the rectangular geometry allows for both highly efficient algorithms and ease of debugging while having no drawback in calculating quantum dot energy levels or the one-dimensional energy bands of nanowires. Since general nanostructure programs can also handle superlattices, it is natural to apply them to these structures as well, but here problems arise due to the fact that the rectangular unit cell is generally not the primitive cell of the superlattice, so that the resulting E(k) relations must be unfolded to obtain the primitive- …
Physics Of Ultrathin-Body Silicon-On-Insulator Schottky-Barrier Field-Effect Transistors, Joachim Knoch, M Zhang, Joerg Appenzeller, S Mantl
Physics Of Ultrathin-Body Silicon-On-Insulator Schottky-Barrier Field-Effect Transistors, Joachim Knoch, M Zhang, Joerg Appenzeller, S Mantl
Other Nanotechnology Publications
In this article we give an overview over the physical mechanisms involved in the electronic transport in ultrathin-body SOI Schottky-barrier MOSFETs. A strong impact of the SOI and gate oxide thickness on the transistor characteristics is found and explained using experimental as well as simulated data. We elaborate on the influence of scattering in the channel and show that for a significant barrier the on-state current is insensitive to scattering once the mean free path for scattering is larger than a characteristic length scale. In addition, recent efforts to lower the Schottky barrier at the source/drain channel interfaces are presented. …
Understanding Coulomb Effects In Nanoscale Schottky-Barrier-Fets, Klaus M. Indlekofer, Joachim Knoch, Joerg Appenzeller
Understanding Coulomb Effects In Nanoscale Schottky-Barrier-Fets, Klaus M. Indlekofer, Joachim Knoch, Joerg Appenzeller
Other Nanotechnology Publications
We employ a novel multiconfigurational self-consistent Green's function approach (MCSCG) for the simulation of nanoscale Schottky-barrier-field-effect transistors (SB-FETs). This approach allows the calculation of electronic transport with a seamless transition from the single-electron regime to room-temperature FET operation. The particular improvement of the MCSCG stems from a self-consistent division of the channel system into a small subsystem of resonantly trapped states for which a many-body Fock space approach becomes numerically feasible and the rest of the system which can be treated adequately on a conventional mean-field level. The Fock space description allows for the calculation of few-electron Coulomb charging effects …
1/F Noise In Carbon Nanotube Devices - On The Impact Of Contacts And Device Geometry, Joerg Appenzeller, Yu-Ming Lin, Joachim Knoch, Zhihong Chen, Phaedon Avouris
1/F Noise In Carbon Nanotube Devices - On The Impact Of Contacts And Device Geometry, Joerg Appenzeller, Yu-Ming Lin, Joachim Knoch, Zhihong Chen, Phaedon Avouris
Other Nanotechnology Publications
We report on the 1/f noise in various ballistic carbon nanotube devices. A common means to characterize the quality of a transistor in terms of noise is to evaluate the ratio of the noise amplitude A and the sample resistance R. By contacting semiconducting tubes with different metal electrodes we are able to show that a small A/R value by itself is no indication of a suitable metal/tube combination for logic applications. We discuss how current in a nanotube transistor is determined by the injection of carriers at the electrode/nanotube interface, while at the same time excess noise is related …
Improved Carrier Injection In Ultrathin-Body Soi Schottky-Barrier Mosfets, M Zhang, Joachim Knoch, Joerg Appenzeller, S Mantl
Improved Carrier Injection In Ultrathin-Body Soi Schottky-Barrier Mosfets, M Zhang, Joachim Knoch, Joerg Appenzeller, S Mantl
Other Nanotechnology Publications
The impact of the gate oxide and the silicon-on-insulator (SOI) body thickness on the electrical performance of SOI Schottky-barrier (SB) MOSFETs with fully nickel silicided source and drain contacts is experimentally investigated. The subthreshold swing S is extracted from the experimental data and serves as a measure for the carrier injection through the Sills. It is shown that decreasing the gate oxide and body thickness allows to strongly increase the carrier injection and hence, a significantly improved ON-state of SB-MOSFETs can be obtained.
Hyperthermic Effects Of Gold Nanorods On Tumor Cells, Terry B. Huff, Ling Tong, Matthew N. Hansen, Ji-Xin Cheng, Alexander Wei
Hyperthermic Effects Of Gold Nanorods On Tumor Cells, Terry B. Huff, Ling Tong, Matthew N. Hansen, Ji-Xin Cheng, Alexander Wei
Other Nanotechnology Publications
Plasmon-resonant gold nanorods, which have large absorption cross sections at near-infrared frequencies, are excellent candidates as multifunctional agents for image-guided therapies based on localized hyperthermia. The controlled modification of the surface chemistry of the nanorods is of critical importance, as issues of cell-specific targeting and nonspecific uptake must be addressed prior to clinical evaluation. Nanorods coated with cetyltrimethylammonium bromide (a cationic surfactant used in nanorod synthesis) are internalized within hours into KB cells by a nonspecific uptake pathway, whereas the careful removal of cetyltrimethylammonium bromide from nanorods functionalized with folate results in their accumulation on the cell surface over the …
Investigation Of Device Parameters For Field-Effect Dna-Sensors By Three-Dimensional Simulation, Eddie Howell, Clemens Heitzinger, Gerhard Klimeck
Investigation Of Device Parameters For Field-Effect Dna-Sensors By Three-Dimensional Simulation, Eddie Howell, Clemens Heitzinger, Gerhard Klimeck
Other Nanotechnology Publications
The development of a DNA field-effect transistor (DNAFET) simulator is described and implications on device structure and future experiments are discussed. In DNAFETs the gate structure is replaced by a layer of immobilized single-stranded DNA molecules which act as surface probe molecules [1, 2]. When complementary DNA strands bind to the receptors, the charge distribution near the surface of the device changes, modulating current transport through the device and enabling detection (cf. Fig. 1 and 5). Arrays of DNAFETs can be used for detecting singlenucleotide polymorphisms and for DNA sequencing. The advantage of DNAFETs over optical methods of detection is …
Ballisticity Of Nanotube Field-Effect Transistors: Role Of Phonon Energy And Gate Bias, Siyuranga O. Koswatta, Sayed Hasan, Mark S. Lundstrom, M. P. Anantram, Dmitri E. Nikonov
Ballisticity Of Nanotube Field-Effect Transistors: Role Of Phonon Energy And Gate Bias, Siyuranga O. Koswatta, Sayed Hasan, Mark S. Lundstrom, M. P. Anantram, Dmitri E. Nikonov
Other Nanotechnology Publications
We investigate the role of electron-phonon scattering and gate bias in degrading the drive current of nanotube field-effect transistors (FETs). Optical phonon scattering significantly decreases the drive current only when gate voltage is higher than a well-defined threshold. For comparable electron-phonon coupling, a lower phonon energy leads to a larger degradation of drive current. Thus in semiconductor nanowire FETs, the drive current will be more sensitive than in carbon nanotube FETs because of the smaller phonon energies in semiconductors. Acoustic phonons and other elastic scattering mechanisms are most detrimental to nanotube FETs irrespective of biasing conditions.
Simulation Of Phonon-Assisted Band-To Band Tunneling In Carbon Nanotube Field-Effect Transistors, Siyuranga O. Koswatta, Mark S. Lundstrom, M. P. Anantram, Dmitri E. Nikonov
Simulation Of Phonon-Assisted Band-To Band Tunneling In Carbon Nanotube Field-Effect Transistors, Siyuranga O. Koswatta, Mark S. Lundstrom, M. P. Anantram, Dmitri E. Nikonov
Other Nanotechnology Publications
Electronic transport in a carbon nanotube metal-oxide-semiconductor field effect transistor (MOSFET) is simulated using the nonequilibrium Green’s functions method with the account of electron-phonon scattering. For MOSFETs, ambipolar conduction is explained via phonon-assisted band-to-band (Landau–Zener) tunneling. In comparison to the ballistic case, we show that the phonon scattering shifts the onset of ambipolar conduction to more positive gate voltage (thereby increasing the off current). It is found that the subthreshold swing in ambipolar conduction can be made as steep as 40 mV/decade despite the effect of phonon scattering.
In Vitro And In Vivo Two-Photon Luminescence Imaging Of Single Gold Nanorods, Haifeng Weng, Terry B. Huff, Daniel A. Zweifel, Wei He, Philip S. Low, Alexander Wei, Ji-Xin Cheng
In Vitro And In Vivo Two-Photon Luminescence Imaging Of Single Gold Nanorods, Haifeng Weng, Terry B. Huff, Daniel A. Zweifel, Wei He, Philip S. Low, Alexander Wei, Ji-Xin Cheng
Other Nanotechnology Publications
Gold nanorods excited at 830 nm on a far-field laser-scanning microscope produced strong two-photon luminescence (TPL) intensities, with a cos(4) dependence on the incident polarization. The TPL excitation spectrum can be superimposed onto the longitudinal plasmon band, indicating a plasmon-enhanced two-photon absorption cross section. The TPL signal from a single nanorod is 58 times that of the two-photon fluorescence signal from a single rhodamine molecule. The application of gold nanorods as TPL imaging agents is demonstrated by in vivo imaging of single nanorods flowing in mouse ear blood vessels.
Theoretical Investigation Of Surface Roughness Scattering In Silicon Nanowire Transistors, Jing Wang, Eric Polizzi, Avik Ghosh, Supriyo Datta, Mark Lundstrom
Theoretical Investigation Of Surface Roughness Scattering In Silicon Nanowire Transistors, Jing Wang, Eric Polizzi, Avik Ghosh, Supriyo Datta, Mark Lundstrom
Other Nanotechnology Publications
Using a full three-dimensional (3D), quantum transport simulator, we theoretically investigate the effects of surface roughness scattering (SRS) on the device characteristics of Si nanowire transistors (SNWTs). The microscopic structure of the Si/SiO2 interface roughness is directly treated by using a 3D finite element technique. The results show that (1) SRS reduces the electron density of states in the channel, which increases the SNWT threshold voltage, and (2) the SRS in SNWTs becomes less effective when fewer propagating modes are occupied, which implies that SRS is less important in small-diameter SNWTs with few modes conducting than in planar metal-oxide-semiconductor field-effect-transistors …
Role Of Phonon Scattering In Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom
Role Of Phonon Scattering In Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom
Other Nanotechnology Publications
The role of phonon scattering in carbon nanotube field-effect transistors CNTFETs is explored by solving the Boltzmann transport equation using the Monte Carlo method. The results show that elastic scattering in a short-channel CNTFET has a small effect on the source-drain current due to the long elastic mean-free path (mfp)(~ 1µm). If elastic scattering with a short mfp were to exist in a CNTFET, the on current would be severely degraded due to the one-dimensional channel geometry. At high drain bias, optical phonon scattering, which has a much shorter mfp (-10 nm), is expected to dominate, even in a short-channel …
Quantum Mechanical Analysis Of Channel Access Geometry And Series Resistance In Nanoscale Transistors, R. Venugopal, S. Goasguen, S. Datta, M. S. Lundstrom
Quantum Mechanical Analysis Of Channel Access Geometry And Series Resistance In Nanoscale Transistors, R. Venugopal, S. Goasguen, S. Datta, M. S. Lundstrom
Other Nanotechnology Publications
We apply a two-dimensional quantum mechanical simulation scheme to study the effect of channel access geometries on device performance. This simulation scheme solves the nonequilibrium Green’s function equations self-consistently with Poisson’s equation and treats the effect of scattering using a simple approximation inspired by Bu ̈ttiker. It is based on an expansion of the device Hamiltonian in coupled mode space. Simulation results are used to highlight quantum effects and discuss the importance of scattering when examining the transport properties of nanoscale transistors with differing channel access geometries. Additionally, an efficient domain decomposition scheme for evaluating the performance of nanoscale transistors …
Performance Projections For Ballistic Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom, Supriyo Datta
Performance Projections For Ballistic Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark Lundstrom, Supriyo Datta
Other Nanotechnology Publications
The performance limits of carbon nanotube field-effect transistors CNTFETs are examined theoretically by extending a one-dimensional treatment used for silicon metal – oxide – semiconductor field-effect transistors MOSFETs. Compared to ballistic MOSFETs, ballistic CNTFETs show similar I–V characteristics but the channel conductance is quantized. For low-voltage, digital applications, the CNTFET with a planar gate geometry provides an on-current that is comparable to that expected for a ballistic MOSFET. Significantly better performance, however, could be achieved with high gate capacitance structures. Because the computed performance limits greatly exceed the performance of recently reported CNTFETs, there is considerable opportunity for progress in …
Resonant Tunneling Through Quantum Dot Arrays, Guanlong Chen, Gerhard Klimeck, Supriyo Datta, Guanhua Chen, William A. Goddard Iii
Resonant Tunneling Through Quantum Dot Arrays, Guanlong Chen, Gerhard Klimeck, Supriyo Datta, Guanhua Chen, William A. Goddard Iii
Birck and NCN Publications
We apply the Hubbard Hamiltonian to describe quantum-dot arrays weakly coupled to two contacts. Exact diagonalization is used to calculate the eigenstates of the arrays containing up to six dots and the linear-response conductance is then calculated as a function of the Fermi energy. In the atomic limit the conductance peaks form two distinct groups separated by the intradot Coulomb repulsion, while in the band limit the peaks occur in pairs. The crossover is studied. A finite interdot repulsion is found to cause interesting rearrangements in the conductance spectrum.
Conductance Spectroscopy In Coupled Quantum Dots, Gerhard Klimeck, Guanlong Chen, Supriyo Datta
Conductance Spectroscopy In Coupled Quantum Dots, Gerhard Klimeck, Guanlong Chen, Supriyo Datta
Birck and NCN Publications
We investigate the linear-response conductance through a pair of coupled quantum dots. The conductance spectrum under ideal conditions is shown to consist of two sets of twin peaks whose locations and amplitudes are determined by the interdot coupling and the intradot charging. We will show that the qualitative features of the spectrum survive against experimental nonidealities such as (1) detuning of the individual dots, (2) interdot charging, (3) inelastic scattering, and (4) multiple lateral states. The effect of higher lateral states depends strongly on the nature of the interaction potential, screening lengths, and exchange terms, but the lowest set of …
Rate Equations For The Phonon Peak In Resonant-Tunneling Structures, Roger Lake, Gerhard Klimeck, J. P. Anantram, Supriyo Datta
Rate Equations For The Phonon Peak In Resonant-Tunneling Structures, Roger Lake, Gerhard Klimeck, J. P. Anantram, Supriyo Datta
Birck and NCN Publications
The ratio of the phonon peak current to the main peak current in double-barrier resonant-tunneling structures is significantly enhanced by barrier asymmetry. Previously, using the Keldysh formalism, we derived analytical expressions, valid in the zero-temperature, high-bias regime, which explained this eftect. We now provide analytical expressions valid for finite temperature and bias obtained from (i) an intuitive derivation using a rate equation approach and (ii) a more general derivation using the Keldysh formalism. The results of the two difFerent approaches are shown to be essentially identical for the ex- perimental device parameters. The finite temperature expressions shed light on the …
Rate Equations From The Keldysh Formalism Applied To The Phonon Peak In Resonant-Tunneling Diodes, Roger Lake, Gerhard Klimeck, Supriyo Datta
Rate Equations From The Keldysh Formalism Applied To The Phonon Peak In Resonant-Tunneling Diodes, Roger Lake, Gerhard Klimeck, Supriyo Datta
Birck and NCN Publications
Starting from the Keldysh formalism, general analytical expressions are derived for the current and the occupation of the well in the presence of inelastic scattering, both at the main peak and at the pho- non peak. These expressions are then evaluated from a continuous coordinate representation of a double-barrier potential profile and also from a tight-binding model of a weakly coupled central site. The resulting expressions are similar, and the analytical expressions derived from the continuous coordi- nate representation compare well with the results obtained from numerical simulations. The analytical expressions and the numerical results show that unlike the main …
Laser Bandwidth-Induced Fluctuations In The Intensity Transmitted By A Fabry-Perot Interferometer, Gerhard Klimeck, Daniel Elliott, M. Hamilton
Laser Bandwidth-Induced Fluctuations In The Intensity Transmitted By A Fabry-Perot Interferometer, Gerhard Klimeck, Daniel Elliott, M. Hamilton
Birck and NCN Publications
We have measured the power spectrum of the intensity Auctuations of light transmitted by a Fabry- Perot interferometer when the input field is the real Gaussian field. The real Gaussian field is a field characterized by real, random (Gaussian) amplitude Auctuations. The bandwidth of the real Gaussian field was varied, taking on values less than that of the interferometer, as well as greater. Comparisons of the measured spectra with calculated spectra are quite satisfactory. Of special interest is a feature in the spectra centered at the laser-interferometer detuning frequency.