We introduce Dynamic Speckle Holography (DSH), a new technique that combines imaging and scattering to measure three dimensional maps of displacements as small as ten nanometers over several centimeters, greatly extending the capabilities of traditional imaging systems. We attain this sensitivity by imaging speckle patterns of light collected at three scattering angles and measuring the decay in the temporal correlation due to local motion. We use DSH to measure the strain field of a colloidal gel undergoing fracture and establish the surprising role of internal tension in driving the fracture.
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Stochastic Speckle Discrimination with Time-tagged Photon Lists: Digging below the Speckle Noise Floor
- Award ID(s):
- 1710385
- PAR ID:
- 10190386
- Date Published:
- Journal Name:
- Publications of the Astronomical Society of the Pacific
- Volume:
- 131
- Issue:
- 1005
- ISSN:
- 0004-6280
- Page Range / eLocation ID:
- 114506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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