PHOTON-ASSISTED TRANSPORT IN CARBON NANOTUBE MESOSCOPIC DEVICE

The aim of the present paper is to investigate the quantum transport properties of a mesoscopic device under the influence of gate voltage and photon energy. A model for such mesoscopic devices is proposed as two metal contacts are deposited on the carbon nanotube quantum dot to serve as source and drain electrodes. The conducting substrate is the gate electrode in this three-terminal mesoscopic device. Another metallic gate is used to govern the electrostatics and the switching of carbon nanotube channel. The substrate at the carbon nanotube quantum dot contacts are controlled by the back gate. Both effects of the photons energy and gate voltage are investigated. The photon-assisted tunneling probability is deduced by solving Dirac equation. Then the current is deduced according to Landauer–Buttiker formula. The quantum capacitance for the device is deduced in terms of density of states. Oscillatory behavior of the current is observed which is due to the Coulomb blockade oscillations. It was found, also, that the peak heights of the dependence of the current on the parameters under study are strongly affected by the interplay between the tunneled electrons and the photon energy. This interplay affects the sidebands resonance. The results obtained in this study are found to be in concordant with those in the literature, which confirm the correctness of the proposed model. This study is valuable for nanotechnology applications, e.g., photodetector devices and solid state quantum computing systems and quantum information processes.

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Multi-Back-Gate Control of Carbon Nanotube Double-Quantum Dot

Japanese Journal of Applied Physics ◽

10.1143/jjap.48.04c201 ◽

2009 ◽

Vol 48 (4) ◽

pp. 04C201 ◽

Cited By ~ 1

Author(s):

Hideyuki Maki ◽

Tomoyuki Mizuno ◽

Satoru Suzuki ◽

Tetsuya Sato ◽

Yoshihiro Kobayashi

Keyword(s):

Carbon Nanotube ◽

Quantum Dot ◽

Double Quantum ◽

Back Gate ◽

Double Quantum Dot ◽

Gate Control

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Monolayer MoS2 field effect transistor with low Schottky barrier height with ferromagnetic metal contacts

Scientific Reports ◽

10.1038/s41598-019-53367-z ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Sachin Gupta ◽

F. Rortais ◽

R. Ohshima ◽

Y. Ando ◽

T. Endo ◽

...

Keyword(s):

Schottky Barrier ◽

Barrier Height ◽

Gate Voltage ◽

Field Effect ◽

Field Effect Transistor ◽

Schottky Barrier Height ◽

Metal Contacts ◽

Back Gate ◽

Vapor Deposition Technique ◽

Effect Transistor

AbstractTwo-dimensional MoS2 has emerged as promising material for nanoelectronics and spintronics due to its exotic properties. However, high contact resistance at metal semiconductor MoS2 interface still remains an open issue. Here, we report electronic properties of field effect transistor devices using monolayer MoS2 channels and permalloy (Py) as ferromagnetic (FM) metal contacts. Monolayer MoS2 channels were directly grown on SiO2/Si substrate via chemical vapor deposition technique. The increase in current with back gate voltage (Vg) shows the tunability of FET characteristics. The Schottky barrier height (SBH) estimated for Py/MoS2 contacts is found to be +28.8 meV (at Vg = 0V), which is the smallest value reported so-far for any direct metal (magnetic or non-magnetic)/monolayer MoS2 contact. With the application of positive gate voltage, SBH shows a reduction, which reveals ohmic behavior of Py/MoS2 contacts. Low SBH with controlled ohmic nature of FM contacts is a primary requirement for MoS2 based spintronics and therefore using directly grown MoS2 channels in the present study can pave a path towards high performance devices for large scale applications.

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Gate-Controlled Tomonaga-Luttinger Liquid and Atomic-Like Behaviors in Peapod Quantum Dots

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.545 ◽

2007 ◽

Vol 121-123 ◽

pp. 545-548

Author(s):

J. Mizubayashi ◽

J. Haruyama ◽

I. Takesue ◽

T. Okazaki ◽

Hisanori Shinohara ◽

...

Keyword(s):

Quantum Dots ◽

Carbon Nanotube ◽

Gate Voltage ◽

Electron Spectroscopy ◽

Luttinger Liquid ◽

Power Laws ◽

Back Gate ◽

Energy Relationships ◽

Quantum Phenomena ◽

A Chain

Anomalously high values of power α (1.6 < α < 12) are found in power laws in conductance versus energy relationships in carbon-nanotube peapod quantum dots, encapsulating a chain of C60 molecules. This power is controllable by the applied back gate voltage. Atomic-like behaviors with doubly degenerate ground states are also found by single electron spectroscopy. They reveal that a portion of power originates from the Tomonaga-Luttinger liquid via the occupied electronic levels, which originate from the subbands unique to the peapods. This observation also clarify that the encapsulated C60 molecules do not directly contribute to the above quantum phenomena in peapods.

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ANTI-RESONANCES IN A NORMAL METAL/SUPERCONDUCTOR JUNCTION WITH A SIDE-COUPLED QUANTUM DOT

International Journal of Modern Physics B ◽

10.1142/s0217979210056943 ◽

2010 ◽

Vol 24 (28) ◽

pp. 5505-5513

Author(s):

ZHENG-YI WU ◽

JIN-FU FENG

Keyword(s):

Quantum Dot ◽

Transport Properties ◽

Single Particle ◽

Gate Voltage ◽

Coulomb Blockade ◽

Andreev Reflection ◽

Normal Metal ◽

Destructive Interference ◽

Channel Network ◽

Calculated Dependence

Using the equivalent single-particle multi-channel network and the Landauer formula, we theoretically study anti-resonances in conductance of a normal metal–superconductor junction with a side-coupled quantum dot. The transport properties depend on the interplay between the Coulomb blockade effect and the Andreev reflection. It is found that the calculated dependence of the conductance on the gate voltage of dot exhibits two anti-resonant conductance dips. This behavior is caused by the destructive interference of the wave directly transmitted through the normal metal–superconductor junction and the wave reflected from the dot. Moreover, we find that the shape of two anti-resonance profile is symmetric, due to the Andreev reflection, depending on the strength of coupling between the quantum dot and normal metal.

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Investigations of Optical Coulomb Blockade Oscillations in Plasmonic Nanoparticle Dimers

International Journal of Photoenergy ◽

10.1155/2022/7771607 ◽

2022 ◽

Vol 2022 ◽

pp. 1-6

Author(s):

Lamessa Gudata ◽

Jule Leta Tesfaye ◽

Abela Saka ◽

R. Shanmugam ◽

L. Priyanka Dwarampudi ◽

...

Keyword(s):

Quantum Dot ◽

Electric Fields ◽

Gate Voltage ◽

Coulomb Blockade ◽

Hot Spot ◽

Plasmonic Nanoparticle ◽

Basic Physics ◽

The Subject ◽

Tunnelling Current ◽

Linear Conductance

The exploration of Coulomb blockade oscillations in plasmonic nanoparticle dimers is the subject of this study. When two metal nanoparticles are brought together at the end of their journey, tunnelling current prevents an infinite connection dipolar plasmon and an infinite amplification in the electric fields throughout the hot spot in between nanoparticles from occurring. One way to think about single-electron tunnelling through some kind of quantum dot is to think about Coulomb blockage oscillations in conductance. The electron transport between the dot and source is considered. The model of study is the linear conductance skilled at describing the basic physics of electronic states in the quantum dot. The linear conductance through the dot is defined as G = lim ⟶ 0 I / V in the limit of infinity of small bias voltage. We discuss the classical and quantum metallic Coulomb blockade oscillations. Numerically, the linear conductance was plotted as a function gate voltage. The Coulomb blockade oscillation occurs as gate voltage varies. In the valleys, the conductance falls exponentially as a function gate voltage. As a result of our study, the conductance is constant at high temperature and does not show oscillation in both positive and negative gate voltages. At low temperature, conductance shows oscillation in both positive and negative gate voltages.

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Current enhancement with alternating gate voltage in the Coulomb-blockade regime of a single-wall carbon nanotube

Applied Physics A ◽

10.1007/s00339-004-2906-5 ◽

2004 ◽

Vol 79 (7) ◽

pp. 1613-1615 ◽

Cited By ~ 1

Author(s):

H.Y. Yu ◽

D.S. Lee ◽

S.S. Kim ◽

B. Kim ◽

S.W. Lee ◽

...

Keyword(s):

Carbon Nanotube ◽

Gate Voltage ◽

Coulomb Blockade ◽

Single Wall Carbon Nanotube ◽

Single Wall Carbon ◽

Coulomb Blockade Regime

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ULTRA-HIGHLY SENSITIVE TERAHERTZ DETECTION USING CARBON-NANOTUBE QUANTUM DOTS

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156407004758 ◽

2007 ◽

Vol 17 (03) ◽

pp. 567-570 ◽

Cited By ~ 1

Author(s):

YUKIO KAWANO ◽

TOMOKO FUSE ◽

KOJI ISHIBASHI

Keyword(s):

Quantum Dots ◽

Carbon Nanotube ◽

Quantum Dot ◽

Coulomb Blockade ◽

Thz Wave ◽

Excess Current ◽

Terahertz Detection ◽

Highly Sensitive ◽

Thz Detector ◽

Coulomb Blockade Regime

We have observed that Terahertz (THz) irradiation to a carbon nanotube quantum dot (CNT-QD) leads to the generation of an excess current in the Coulomb blockade regime. It was found that this THz detected signal survives even when the incident THz wave is extremely weak (~1 fW). This means that the CNT-QD could works as a highly sensitive THz detector.

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MAGNETIC FIELD, PRESSURE AND TEMPERATURE DEPENDENT OPTICAL PROPERTIES IN A GaAs 9.0 P 1.0 QUANTUM DOT

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v6i2.1791 ◽

2014 ◽

Vol 6 (2) ◽

pp. 1178-1190

Author(s):

A. JOHN PETER ◽

Ada Vinolin

Keyword(s):

Magnetic Field ◽

Optical Properties ◽

Quantum Dot ◽

Field Strength ◽

Magnetic Field Strength ◽

Photon Energy ◽

Nonlinear Optical ◽

Binding Energies ◽

Nonlinear Optical Properties ◽

Optical Rectification

Simultaneous effects of magnetic field, pressure and temperature on the exciton binding energies are found in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot. Numerical calculations are carried out taking into consideration of spatial confinement effect. The cylindrical system is taken in the present problem with the strain effects. The electronic properties and the optical properties are found with the combined effects of magnetic field strength, hydrostatic pressure and temperature values. The exciton binding energies and the nonlinear optical properties are carried out taking into consideration of geometrical confinement and the external perturbations.Compact density approach is employed to obtain the nonlinear optical properties. The optical rectification coefficient is obtained with the photon energy in the presence of pressure, temperature and external magnetic field strength. Pressure and temperature dependence on nonlinear opticalÂ susceptibilities of generation of second and third order harmonics as a function of incident photon energy are brought out in the influence of magnetic field strength. The result shows that the electronic and nonlinear optical properties are significantly modified by the applications of external perturbations in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot.

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