Coulomb blockade threshold in inhomogeneous one-dimensional arrays of tunnel junctions

Melsen, J. A.; Hanke, Ulrik; Müller, H. J.; Chao, K. A.

doi:10.1103/physrevb.55.10638

Cited by 40 publications

(52 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The threshold voltage is given by V T = min k V k T . As pointed out by Melsen et al, the Coulomb blockade region increases as the number of junctions, N , increases [16] as shown in Figs. 2(a) and 2(b).…”

Section: (D)mentioning

confidence: 60%

See 1 more Smart Citation

Coulomb staircase in STM current through granular films

et al. 2000

View full text Add to dashboard Cite

The electron transport through an array of tunnel junctions consisting of an STM tip and a granular film is studied both theoretically and experimentally. When the tunnel resistance between the tip and a granule on the surface is much larger than those between granules, a bottleneck of the tunneling current is created in the array. It is shown that the period of the Coulomb staircase(CS) is given by the capacitance at the bottleneck. Our STM experiments on Co-Al-O granular films show the CS with a single period at room temperature. This provides a new possibility for single-electron-spinelectronic devices at room temperature.Charging effects on single electron tunneling such as Coulomb blockade and Coulomb oscillation have attracted much interest [1]. Recent advances in nanotechnology enable us to fabricate small tunnel junctions where charging effects play an essential role. The I-V characteristics for double tunnel junction systems have been extensively studied, where the step-like structure called Coulomb staircase(CS) is observed when the resistances between the junctions are not equal [1]. For these asymmetric double junction systems, the junction with a large resistance behaves like a bottleneck of the tunneling current and the central island is charged through the other junction up to the maximum charge. The tunneling current jumps when the maximum charge changes. Recently, the CS has been observed by using a tip of scanning tunneling microscope(STM) of nanometer-size in highly resistive granular films [2-5] as well as metaldroplet systems [6,7]. For a granular film, which is considered to be an array of tunnel junctions, the observed CS implies that a bottleneck exists in the conducting paths. However, the physics behind the CS in a granular film is not clear because it contains many granules with different size and the conducting path may form a three-dimensional network in a thick granular film.Bar-Sadeh et al. have studied the STM current through a nonmagnetic granular film, Au-Al 2 O 3 , by using the cryogenic STM [2,3]. They observed the CS at temperatures T = 4.2 and 78 K, and analyzed the experimental data by using a triple barrier model. They assumed that the rate for tunneling between two granules is small and the number of excess electrons in each granule is treated independently. Because of these assumptions, the CS was given by the superposition of two different periods in their model: one was determined by the tunnel process between the STM tip and a granule, the other between another granule and the base electrode. On the contrary, as we will show later, the CS has a single period which is determined by the capacitance at the bottleneck.In this Letter, we study the electron transport through an array of tunnel junctions consisting of an STM tip and a granular film both theoretically and experimentally. In this system, we can vary the tunnel resistance between the tip and a granule on the surface by changing the distance between them. When the tunnel resistance between the tip and a granule ...

show abstract

Section: (D)mentioning

confidence: 60%

“…2(a) and 2(b), we present the numerical results for tunnel junctions with N = 2 ∼ 5 at T = 0, N being the number of junctions. Due to the charging energy in each junction, single electron tunneling is blocked as long as the bias voltage V is lower than the threshold value V T [16]. From Eq.…”

Section: (D)mentioning

confidence: 99%

Coulomb staircase in STM current through granular films

et al. 2000

View full text Add to dashboard Cite

show abstract

“…However, as long as only the blockade voltage V b is considered, it is independent of the choice of the resistances. 5 This is because the determination of V b poses an electrostatic problem without flowing current. A constant tunnel resistance of 500 k⍀ is used for each tunnel junction and the independence of the outcome of this value was checked numerically.…”

Section: Employed Methodsmentioning

confidence: 99%

“…In one-dimensional arrays, the influence of offset charge on V b has been studied both experimentally 3,4 and theoretically. 5 The current dependence Iϰ(VϪV b ) resulting from the effect of background charges was suggested 6 using ϭ1 in case of one-dimensional arrays, and ϭ5/3 in case of two-dimensional networks. That work has spawned a number of experiments [7][8][9][10][11] with in part different values of .…”

Section: Introductionmentioning

confidence: 99%

Effects of disorder on the blockade voltage of two-dimensional quantum dot arrays

Müller¹,

Katayama²,

Mizuta³

1998

Journal of Applied Physics

View full text Add to dashboard Cite

The influence of both geometric and offset charge disorder of two-dimensional quantum dot arrays ͑also known as network tunnel junctions͒ on their Coulomb blockade voltage V b is studied using extensive Monte-Carlo simulations. A general increase of V b with increasing disorder is confirmed, but an exception to the rule is found for intermediate degrees of offset charge disorder. Detailed studies of the V b distribution reveal a stability of its minimal value against geometric disorder, whereas this figure is considerably increased for high offset charge disorder. Implications of our results for single electron device design are discussed.

show abstract

“…Electronic transport in nonmagnetic SETs was already extensively studied in the past two decades [14,15,79,80,81,82,83,84,85,86,87,88,89]. Recently, the attention was also drawn to electron tunnelling in magnetic systems [25,26,73,74,90,91,92], which was stimulated by recent progress in nanotechnology.…”

Section: Ferromagnetic Single-electron Transistors Based On Metallic mentioning

confidence: 99%

Spin effects in single-electron tunnelling

Barnaś¹,

Weymann²

2008

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

Abstract. An important consequence of the discovery of giant magnetoresistance in metallic magnetic multilayers is a broad interest in spin dependent effects in electronic transport through magnetic nanostructures. An example of such systems are tunnel junctions -single-barrier planar junctions or more complex ones. In this review we present and discuss recent theoretical results on electron and spin transport through ferromagnetic mesoscopic junctions including two or more barriers. Such systems are also called ferromagnetic single-electron transistors. We start from the situation when the central part of a device has the form of a magnetic (or nonmagnetic) metallic nanoparticle. Transport characteristics reveal then single-electron charging effects, including the Coulomb staircase, Coulomb blockade, and Coulomb oscillations. Single-electron ferromagnetic transistors based on semiconductor quantum dots and large molecules (especially carbon nanotubes) are also considered. The main emphasis is placed on the spin effects due to spin-dependent tunnelling through the barriers, which gives rise to spin accumulation and tunnel magnetoresistance. Spin effects also occur in the current-voltage characteristics, (differential) conductance, shot noise, and others. Transport characteristics in the two limiting situations of weak and strong coupling are of particular interest. In the former case we distinguish between the sequential tunnelling and cotunnelling regimes. In the strong coupling regime we concentrate on the Kondo phenomenon, which in the case of transport through quantum dots or molecules leads to an enhanced conductance and to a pronounced zero-bias Kondo peak in the differential conductance.

show abstract

Coulomb blockade threshold in inhomogeneous one-dimensional arrays of tunnel junctions

Cited by 40 publications

References 20 publications

Coulomb staircase in STM current through granular films

Coulomb staircase in STM current through granular films

Effects of disorder on the blockade voltage of two-dimensional quantum dot arrays

Spin effects in single-electron tunnelling

Contact Info

Product

Resources

About