Gold nanostructures created by highly charged ions

Pomeroy, Joshua M.; Perrella, A. C.; Grube, Holger; Gillaspy, John D.

doi:10.1103/physrevb.75.241409

Cited by 31 publications

(19 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the case of CaF 2 , the good agreement with model calculations based on a twotemperature-model [3] suggests, that the transfer of the primary electronic excitation to the lattice by electronphonon-coupling is the origin of the structural modifications. For conductive materials, however, the situation is less clear as experimental evidence is sparse [5,6] and inconclusive. One way to investigate the fundamental interaction mechanisms of HCI with conductive targets is to use crystalline graphite.…”

mentioning

confidence: 99%

Damage in graphene due to electronic excitation induced by highly charged ions

Hopster¹,

Kozubek²,

Ban-d’Etat³

et al. 2014

2D Mater.

View full text Add to dashboard Cite

Graphene is expected to be rather insensitive to ionizing particle radiation. We demonstrate that single layers of exfoliated graphene sustain significant damage from irradiation with slow highly charged ions. We have investigated the ion induced changes of graphene after irradiation with highly charged ions of different charge states (q = 28-42) and kinetic energies (E kin = 150-450 keV). Atomic force microscopy images reveal that the ion induced defects are not topographic in nature but are related to a significant change in friction. To create these defects, a minimum charge state is needed. In addition to this threshold behaviour, the required minimum charge state as well as the defect diameter show a strong dependency on the kinetic energy of the projectiles. From the linear dependency of the defect diameter on the projectile velocity we infer that electronic excitations triggered by the incoming ion in the above-surface phase play a dominant role for this unexpected defect creation in graphene. PACS numbers:The bombardment of surfaces with highly charged ions (HCI) offers an elegant way to deposit a large amount of energy into a very small volume and to study the behaviour of solid matter under such extreme conditions. In contrast to singly charged ions, HCI store a considerable amount of potential energy E pot (defined as the energy to remove the electrons from the initial atom to infinity). Upon impact they trigger significant electronic excitations in the near surface region, which can result in a variety of nanoscaled structural modifications [1]. For two dielectric materials, CaF 2 and KBr, the dependency of the structural surface modification on the charge state q and the kinetic energy E kin of the projectile was investigated in great detail [2][3][4] and could be explained in terms of different phase transitions and defect agglomeration mechanisms, respectively. In the case of CaF 2 , the good agreement with model calculations based on a twotemperature-model [3] suggests, that the transfer of the primary electronic excitation to the lattice by electronphonon-coupling is the origin of the structural modifications. For conductive materials, however, the situation is less clear as experimental evidence is sparse [5,6] and inconclusive. One way to investigate the fundamental interaction mechanisms of HCI with conductive targets is to use crystalline graphite. It can be used either in its bulk form (highly oriented pyrolytic graphite, HOPG) or in its two-dimensional (2D) form, graphene. Chemically identical, graphene shows superior electronic and heat transfer properties. As a consequence, it has even been proposed that graphene should be virtually transparent to energetic ions [7].In this paper we show, that graphene sustains significant damage even by individual HCI impacts. We demonstrate that HCI irradiation can be used to create regions of enhanced friction, which we attribute to chemical changes of the graphene lattice and whose size can be easily controlled. We present evidence that this damage is...

show abstract

mentioning

confidence: 99%

Damage in graphene due to electronic excitation induced by highly charged ions

Hopster¹,

Kozubek²,

Ban-d’Etat³

et al. 2014

2D Mater.

View full text Add to dashboard Cite

show abstract

“…Recently, HCI induced hillock structures have been observed on CaF 2 which have been explained by a solidliquid phase transition at the surface induced solely by the excitation from the potential energy [12]. For metallic systems the potential energy dissipation was found to contribute less effectively to surface nanostructuring [13].…”

mentioning

confidence: 99%

Defect Mediated Desorption of the KBr(001) Surface Induced by Single Highly Charged Ion Impact

et al. 2008

View full text Add to dashboard Cite

The individual impacts of slow (300 eV/amu) highly charged Xe ions induce nanometer sized pitlike structures on the KBr (001) surface. The volume of these structures shows a strong dependence on the ions potential energy. Total potential sputter yields from atomically flat (001) terraces are determined by imaging single ion impact sites. The dependence of the sputter yield on the ions initial charge state combined with structure formation at low and high-fluence irradiations indicates that agglomeration of defects into complex centers plays a major role in the desorption process induced by the potential energy.

show abstract

“…All tunnel junctions (TJs) described have the same basic structure and fabrication method in common, see Ref. 12 for more details. The TJs in this study are nearly 2D devices of sizes ≈ 50 µm x 50 µm composed of two metallic multi-layers with a total thickness ≈ 30 nm separated by an aluminum oxide tunnel barrier typically between 1 nm and 2 nm in thickness, depending on the study.…”

Section: Samplesmentioning

confidence: 99%

“…This report reviews recent progress made at the National Institute of Standards and Technology (NIST) Electron Beam Ion Trap (EBIT) facility studying the efficacy of modifying ultra-thin electron tunnel barriers using HCIs. Many years of the fundamental studies of HCI-target interactions performed by several groups worldwide enable this effort; due to space limitations, only a few representative citations throughout will be provided to allow the avid reader to explore the field [3][4][5][6][7][8][9][10] . Generally, previous work shows that metals have weak potential (neutralization) energy sputtering (PES), good insulators have dramatic PES, and complex materials in between have complex energy dissipation chains that do not always lead to strong PES, but typically have large secondary electron yields.…”

Section: Introductionmentioning

confidence: 99%

Highly Charged Ion (HCI) Modified Tunnel Junctions

Pomeroy

Grube²

2009

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

The neutralization energy carried by highly charged ions (HCIs) provides an alternative method for localizing energy on a target's surface, producing features and modifying surfaces with fluences and kinetic energy damage that are negligible compared to singly ionized atoms. Since each HCI can deposit an enormous amount of energy into a small volume of the surface (e.g., Xe 44+ delivers 51 keV of neutralization energy per HCI), each individual HCI's interaction with the target can produce a nanoscale feature. Many studies of HCI-surface features have characterized some basic principles of this unique ion-surface interaction, but the activity reported here has been focused on studying ensembles of HCI features in ultra-thin insulating films by fabricating multi-layer tunnel junction devices. The ultra-thin insulating barriers allow current to flow by tunneling, providing a very sensitive means of detecting changes in the barrier due to highly charged ion irradiation and, conversely, HCI modification provides a method of finely tuning the transparency of the tunnel junctions that spans several orders of magnitude for devices produced from a single process recipe. Systematic variation of junction bias, temperature, magnetic field and other parameters provides determination of the transport mechanism, defect densities, and magnetic properties of these nano-features and this novel approach to device fabrication.

show abstract

Gold nanostructures created by highly charged ions

Cited by 31 publications

References 22 publications

Damage in graphene due to electronic excitation induced by highly charged ions

Damage in graphene due to electronic excitation induced by highly charged ions

Defect Mediated Desorption of the KBr(001) Surface Induced by Single Highly Charged Ion Impact

Highly Charged Ion (HCI) Modified Tunnel Junctions

Contact Info

Product

Resources

About