### Abstract

Because liquids cannot resist shear except over very short distances comparable to the atomic spacing, shear sound waves (i.e., transverse phonons) propagate only for very short wavelengths. A measure of this limit is the cutoff wave number k _{c}, which is sometimes called the critical wave number. Previously k _{c} was determined in molecular dynamics (MD) simulations by obtaining the dispersion relation. Another approach is developed in this paper by identifying the wave number at the onset of a negative peak in the transverse current correlation function. This method is demonstrated using a three-dimensional MD simulation of a Yukawa fluid, which mimics dusty plasmas. In general, k _{c} is an indicator of conditions where elastic and dissipative effects are approximately balanced. Additionally, the crossover frequency for the real and imaginary terms of the complex viscosity of a dusty plasma is obtained; this crossover frequency corresponds to the Maxwell relaxation time.

Original language | English |
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Article number | 066401 |

Journal | Physical Review E - Statistical, Nonlinear, and Soft Matter Physics |

Volume | 85 |

Issue number | 6 |

DOIs | |

Publication status | Published - Jun 11 2012 |

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### ASJC Scopus subject areas

- Condensed Matter Physics
- Statistical and Nonlinear Physics
- Statistics and Probability

### Cite this

*Physical Review E - Statistical, Nonlinear, and Soft Matter Physics*,

*85*(6), [066401]. https://doi.org/10.1103/PhysRevE.85.066401

**Cutoff wave number for shear waves and Maxwell relaxation time in Yukawa liquids.** / Goree, J.; Donkó, Z.; Hartmann, P.

Research output: Contribution to journal › Article

*Physical Review E - Statistical, Nonlinear, and Soft Matter Physics*, vol. 85, no. 6, 066401. https://doi.org/10.1103/PhysRevE.85.066401

}

TY - JOUR

T1 - Cutoff wave number for shear waves and Maxwell relaxation time in Yukawa liquids

AU - Goree, J.

AU - Donkó, Z.

AU - Hartmann, P.

PY - 2012/6/11

Y1 - 2012/6/11

N2 - Because liquids cannot resist shear except over very short distances comparable to the atomic spacing, shear sound waves (i.e., transverse phonons) propagate only for very short wavelengths. A measure of this limit is the cutoff wave number k c, which is sometimes called the critical wave number. Previously k c was determined in molecular dynamics (MD) simulations by obtaining the dispersion relation. Another approach is developed in this paper by identifying the wave number at the onset of a negative peak in the transverse current correlation function. This method is demonstrated using a three-dimensional MD simulation of a Yukawa fluid, which mimics dusty plasmas. In general, k c is an indicator of conditions where elastic and dissipative effects are approximately balanced. Additionally, the crossover frequency for the real and imaginary terms of the complex viscosity of a dusty plasma is obtained; this crossover frequency corresponds to the Maxwell relaxation time.

AB - Because liquids cannot resist shear except over very short distances comparable to the atomic spacing, shear sound waves (i.e., transverse phonons) propagate only for very short wavelengths. A measure of this limit is the cutoff wave number k c, which is sometimes called the critical wave number. Previously k c was determined in molecular dynamics (MD) simulations by obtaining the dispersion relation. Another approach is developed in this paper by identifying the wave number at the onset of a negative peak in the transverse current correlation function. This method is demonstrated using a three-dimensional MD simulation of a Yukawa fluid, which mimics dusty plasmas. In general, k c is an indicator of conditions where elastic and dissipative effects are approximately balanced. Additionally, the crossover frequency for the real and imaginary terms of the complex viscosity of a dusty plasma is obtained; this crossover frequency corresponds to the Maxwell relaxation time.

UR - http://www.scopus.com/inward/record.url?scp=84862169130&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84862169130&partnerID=8YFLogxK

U2 - 10.1103/PhysRevE.85.066401

DO - 10.1103/PhysRevE.85.066401

M3 - Article

AN - SCOPUS:84862169130

VL - 85

JO - Physical review. E

JF - Physical review. E

SN - 2470-0045

IS - 6

M1 - 066401

ER -