Single nanowire manipulation within dielectrophoretic force fields in the sub-crossover frequency regime

Abstract

This paper presents the quantitative relationship between the control parameters of a dielectrophoretic (DEP) force field and the resulting electrokinetic region of influence experienced by individual nanowires (NWs) in colloidal suspensions. Our results show that DEP operation at sub-crossover frequencies, which are defined as frequencies slightly below the transition from positive-to-negative DEP, offers a suitable but previously unexplored performance regime for single NW manipulation and assembly. The low-magnitude DEP forces at these frequencies, which are estimated to be 8 orders of magnitude smaller as compared to near-DC frequencies, provide an efficient avenue to controllably extend electrokinetic influence on suspension volumes that present isolated NWs. These results are demonstrated using α-phase manganese dioxide NWs as a model one-dimensional construct. Based on experimentally extracted values for the NW intrinsic conductivity and dielectric permittivity, we employ computational models to explain each of the performance regimes observed in this nanoassembly system. In addition, we use a new approach to estimate the concentration of a NW suspension from experimentally observed data for deposition yields.

Brittle fracture to recoverable plasticity: polytypism-dependent nanomechanics in todorokite-like nanobelts

“…Further details on this technique can be found in our past reports, where this approach has been employed to assemble and characterize the physical properties of other one-dimensional nanomaterials. [21][22][23][24] As shown in Fig. 2(a and b), each device consists of a pair of 150 nm thick gold nanoelectrodes, which are separated by a design gap of either 600 nm or 1 mm in different designs.…”

Super-giant magnetoresistance at room-temperature in copper nanowires due to magnetic field modulation of potential barrier heights at nanowire-contact interfaces

“…This polarized the Cu nanowires in the suspension and exerted a dielectrophoretic (DEP) force that caused them to be captured across the nanoelectrodes. By tuning the excitation voltage (4V, peak-to-peak) and its frequency (1 kHz) over a given deposition period (4 minutes), the DEP region of influence was controlled to extend over suspension volumes that present single or a few nanowires [11]. This resulted in an array of devices on the chip with a single or a few nanowires assembled across the Au nanoelectrodes.…”

Young’s modulus of [111] germanium nanowires

“…2(a)). [14][15][16][17] The gold nanoelectrodes were defined as a part of an array of devices on silicon substrates. The DEP parameters such as voltage, time, and frequency were optimized to yield either a single or a few non-overlapping nanowires at each device location in the electrode array.…”