Direct Measurement of Dendritic Array Stability
- Department of Physics, City College of the City University of New York, New York, New York, 10031 (United States)
- Departamento de Fisica, ICEX, Universidade Federal de Minas Gerais, Belo Horizonte, 30123-970, Minas Gerais (Brazil)
Stability of a uniformly spaced dendritic array against a spatial period doubling instability was studied through UV thermal perturbations of every other dendrite tip. We observed that above a critical pulling speed the array is stable against these perturbations and we measured decreasing decay rates of the perturbed mode as we approached the critical speed. In the linear regime, our measurements are qualitatively consistent with the Warren-Langer linear stability analysis for a dendritic array [J.thinspA. Warren and J.thinspS. Langer, Phys.thinspthinspRev.thinspthinspA {bold 42}, 3518 (1990); Phys.thinspthinspRev.thinspthinspE {bold 47}, 2702 (1993)], while in the nonlinear regime fitting to a third order amplitude equation shows that the transition is subcritical. {copyright} {ital 1998} {ital The American Physical Society}
- DOE Contract Number:
- FG02-84ER45132
- OSTI ID:
- 638818
- Journal Information:
- Physical Review Letters, Vol. 81, Issue 2; Other Information: PBD: Jul 1998
- Country of Publication:
- United States
- Language:
- English
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