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Squeezing millimeter waves through a single, nanometer-wide, centimeter-long slit.

ABSTRACT: We demonstrate broadband non-resonant squeezing of terahertz (THz) waves through an isolated 2-nm-wide, 2-cm-long slit (aspect ratio of 10(7)), representing a maximum intensity enhancement factor of one million. Unlike resonant nanogap structures, a single, effectively infinitely-long slit passes incident electromagnetic waves with no cutoff, enhances the electric field within the gap with a broad 1/f spectral response, and eliminates interference effects due to finite sample boundaries and adjacent elements. To construct such a uniform, isolated slit that is much longer than the millimeter-scale spot of a THz beam, we use atomic layer lithography to pattern vertical nanogaps in a metal film over an entire 4-inch wafer. We observe an increasing field enhancement as the slit width decreases from 20 nm to 2 nm, in agreement with numerical calculations.

SUBMITTER: Chen X

PROVIDER: S-EPMC4208056 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Nanometer to millimeter scale peptide-porphyrin materials.

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ADDITIVE EFFECTS OF MILLIMETER WAVES AND 2 DEOXYGLUCOSE CO-EXPOSURE ON THE HUMAN KERATINOCYTE TRANSCRIPTOME

Project description:To evaluate the effect of millimeter waves (MMW) exposure on the gene expression, we have employed whole genome microarray expression profiling. Neonatal primary Keratinocyte cells pooled from 3 healthy donors were exposed ex vivo, by 60.4 GHz-MMW, at an incident power density (IPD) of 20 mW/cm² (3 hours of treatment in athermic condition).No modification of keratinocyte transcriptome was observed. Considering that MMW could also impact the cell metabolism, we assessed then effect of glycolysis inhibitor 2 deoxyglucose treatment (2dG, 20 mM during 3 hours) in association with MMW co-exposure. 2dG treatment induces a high modification of the transcriptome (632 coding genes). Genes affected in their expression are linked with transcriptional repression, cellular communication and endoplasmic reticulum homeostasis. The MMW/2dG co-exposition induced a slight modification of cell transcriptome, which reflects the capacity of MMW to interfere with bioenergetic stress response. After RT-PCR validation, 6 genes (SOCS3, SPRY2, TRIB1, FAM46A, CSRNP1 and PPP1R15A) were confirmed as sensitive to MMW exposure during 2dG treatment.

2016-09-20 | GSE83829 | GEO

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