Crystalline silicon core fibres from aluminium core preforms

Abstract

Traditional fibre-optic drawing involves a thermally mediated geometric scaling where both the fibre materials and their relative positions are identical to those found in the fibre preform. To date, all thermally drawn fibres are limited to the preform composition and geometry. Here, we fabricate a metre-long crystalline silicon-core, silica-cladded fibre from a preform that does not contain any elemental silicon. An aluminium rod is inserted into a macroscopic silica tube and then thermally drawn. The aluminium atoms initially in the core reduce the silica, to produce silicon atoms and aluminium oxide molecules. The silicon atoms diffuse into the core, forming a large phase-separated molten silicon domain that is drawn into the crystalline silicon core fibre. The ability to produce crystalline silicon core fibre out of inexpensive aluminium and silica could pave the way for a simple and scalable method of incorporating silicon-based electronics and photonics into fibres.

Semiconductor optical fibers for nonlinear applications

“…9,10 This technique is more practical in that it is capable of producing much longer lengths of fiber in a single fabrication step, and thus has been more widely adopted by the community. [11][12][13][14] The only significant drawback of this method is that the high temperatures used to heat and draw the fiber place some restrictions on the choice of core/cladding material combinations and can also limit the core sizes to be hundreds of microns in diameter due to oxygen contamination. Though this latter issue has been somewhat mitigated recently via the introduction of interfacial modifiers at the core/cladding boundary.…”

Hybrid Optical Fibers – An Innovative Platform for In‐Fiber Photonic Devices

“…This was recently highlighted in work where an aluminium rod inside a silica cladding at the preform level resulted in a Silicon core and alumina domains in the fi ber. [ 128 ] Extensive work has also been performed to elucidate and control nucleation and grain growth, in order to extend the length of single crystal domains along the fi ber axis. [129][130][131] Note also that Se and Te cores have recently been co-drawn inside phosphate glasses, which paves the way towards integrating semiconducting materials at a novel temperature range.…”

“…[ 106,128,133 ] During thermal drawing, materials Figure 14. a) SEM micrograph of a solid chalcogenide glass core (As 52 Se 40 Te 8 ) fi ber after a post-drawing thermal annealing treatment that exhibits crystal growth nucleating for the most part from the interfacing crystalline electrodes.…”

Light trapping in horizontally aligned silicon microwire solar cells

“…Silica-clad silicon microwires were fabricated using the interface modifier described by Nordstrand, et al [20], via the molten core fiber drawing method [2,[21][22][23]] employing a conventional fiber tower. Bulk quantities of wires with a silicon core to silica clad outer diameter …”