dorsal/arxiv
View SchemaHeterodyne interferometer with unequal path lengths
| Authors | Deepak Kumar, Paul M. Bellan |
|---|---|
| Categories | |
| ArXiv ID | physics/0608082 |
| URL | https://arxiv.org/abs/physics/0608082 |
| DOI | 10.1063/1.2336769 |
Abstract
Laser interferometry is an extensively used diagnostic for plasma experiments. Existing plasma interferometers are designed on the presumption that the scene and reference beam path lengths have to be equal, a requirement that is costly in both the number of optical components and the alignment complexity. It is shown here that having equal path lengths is not necessary - instead what is required is that the path length difference be an even multiple of the laser cavity length. This assertion has been verified in a heterodyne laser interferometer that measures typical line-average densities of $\sim 10^{21}/\textrm{m}^2$ with an error of $\sim 10^{19}/\textrm{m}^2$.
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"abstract": "Laser interferometry is an extensively used diagnostic for plasma\nexperiments. Existing plasma interferometers are designed on the presumption\nthat the scene and reference beam path lengths have to be equal, a requirement\nthat is costly in both the number of optical components and the alignment\ncomplexity. It is shown here that having equal path lengths is not necessary -\ninstead what is required is that the path length difference be an even multiple\nof the laser cavity length. This assertion has been verified in a heterodyne\nlaser interferometer that measures typical line-average densities of $\\sim\n10^{21}/\\textrm{m}^2$ with an error of $\\sim 10^{19}/\\textrm{m}^2$.",
"arxiv_id": "physics/0608082",
"authors": [
"Deepak Kumar",
"Paul M. Bellan"
],
"categories": [
"physics.plasm-ph"
],
"doi": "10.1063/1.2336769",
"title": "Heterodyne interferometer with unequal path lengths",
"url": "https://arxiv.org/abs/physics/0608082"
},
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