### Abstract

We have measured the temperature and magnetic field dependencies of the zero bias resistance for several 2D arrays of small aluminum Josephson junctions. The normal state resistances R_{N} of the junctions vary between 2.2 and 7.5 kω whereas the ratio of Josephson coupling energy E_{J} to the charging energy E_{c} ranges between 4.3 and 0.6, where E_{c}= e^{2} 2C, C being the junction capacitance. The vortex mobility is deduced from the frustration (i.e. the number of flux quantum per unit cell) dependence of zero bias resistance. The mobility decreases when the temperature is lowered, resulting in a decrease of resistance. Fitting the data to a simple exponential form, we find the barrier for the vortex hopping to be -aE_{J}, with a≈0.3. For all arrays, there exists a crossover temperature T_{cr} which separates the regime of thermally assisted hopping from that of quantum creep of vortices. For our samples, T_{cr} is close to the theoretically predicted value of ω_{p} 2π, where ω_{p}=(8E_{J}E_{c})^{ 1 2}.

Original language | English |
---|---|

Pages (from-to) | 989-990 |

Number of pages | 2 |

Journal | Physica B: Physics of Condensed Matter |

Volume | 194-196 |

Issue number | PART 1 |

DOIs | |

Publication status | Published - Feb 2 1994 |

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### All Science Journal Classification (ASJC) codes

- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering

### Cite this

*Physica B: Physics of Condensed Matter*,

*194-196*(PART 1), 989-990. https://doi.org/10.1016/0921-4526(94)90824-9

**Vortex mobility in two-dimensional arrays of small Josephson junctions.** / Chen, C. D.; Delsing, P.; Haviland, D. B.; Harada, Y.; Claeson, T.

Research output: Contribution to journal › Article

*Physica B: Physics of Condensed Matter*, vol. 194-196, no. PART 1, pp. 989-990. https://doi.org/10.1016/0921-4526(94)90824-9

}

TY - JOUR

T1 - Vortex mobility in two-dimensional arrays of small Josephson junctions

AU - Chen, C. D.

AU - Delsing, P.

AU - Haviland, D. B.

AU - Harada, Y.

AU - Claeson, T.

PY - 1994/2/2

Y1 - 1994/2/2

N2 - We have measured the temperature and magnetic field dependencies of the zero bias resistance for several 2D arrays of small aluminum Josephson junctions. The normal state resistances RN of the junctions vary between 2.2 and 7.5 kω whereas the ratio of Josephson coupling energy EJ to the charging energy Ec ranges between 4.3 and 0.6, where Ec= e2 2C, C being the junction capacitance. The vortex mobility is deduced from the frustration (i.e. the number of flux quantum per unit cell) dependence of zero bias resistance. The mobility decreases when the temperature is lowered, resulting in a decrease of resistance. Fitting the data to a simple exponential form, we find the barrier for the vortex hopping to be -aEJ, with a≈0.3. For all arrays, there exists a crossover temperature Tcr which separates the regime of thermally assisted hopping from that of quantum creep of vortices. For our samples, Tcr is close to the theoretically predicted value of ωp 2π, where ωp=(8EJEc) 1 2.

AB - We have measured the temperature and magnetic field dependencies of the zero bias resistance for several 2D arrays of small aluminum Josephson junctions. The normal state resistances RN of the junctions vary between 2.2 and 7.5 kω whereas the ratio of Josephson coupling energy EJ to the charging energy Ec ranges between 4.3 and 0.6, where Ec= e2 2C, C being the junction capacitance. The vortex mobility is deduced from the frustration (i.e. the number of flux quantum per unit cell) dependence of zero bias resistance. The mobility decreases when the temperature is lowered, resulting in a decrease of resistance. Fitting the data to a simple exponential form, we find the barrier for the vortex hopping to be -aEJ, with a≈0.3. For all arrays, there exists a crossover temperature Tcr which separates the regime of thermally assisted hopping from that of quantum creep of vortices. For our samples, Tcr is close to the theoretically predicted value of ωp 2π, where ωp=(8EJEc) 1 2.

UR - http://www.scopus.com/inward/record.url?scp=0039521431&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0039521431&partnerID=8YFLogxK

U2 - 10.1016/0921-4526(94)90824-9

DO - 10.1016/0921-4526(94)90824-9

M3 - Article

AN - SCOPUS:0039521431

VL - 194-196

SP - 989

EP - 990

JO - Physica B: Condensed Matter

JF - Physica B: Condensed Matter

SN - 0921-4526

IS - PART 1

ER -