Piezoelectric and Dielectric Properties of LiNbO3, PMN-PT, and PZT-5A Materials at Cryogenic Temperatures

• Author / Creator

  Md Shahidul Islam

• The piezoelectric coecients dij , dielectric constant K
  ij , dielectric loss, creep and
  hysteresis were measured for 41 X-cut lithium niobate (LiNbO3), single crystal lead
  magnesium niobate-lead titanate (PMN-PT) and ceramic lead zirconium titanate
  (PZT-5A) transducers. The measurements were made between room temperature and
  78 mK. The magnitude and temperature dependence of the three materials' properties
  can be understood in terms of intrinsic and extrinsic mechanisms in single crystals
  and ceramics. Several new features were observed, including a direct connection
  between creep and hysteresis, a unique region of negative creep in PMN-PT, and a
  surprisingly strong low-temperature dependence of d15 for PMN-PT and PZT, that
  extends well below 1 K. The strong low-temperature dependence of d15 PMN-PT
  and PZT suggests that there must be a wide range of small energy scales involved in
  domain wall motion. The hysteresis and creep in PMN-PT extend to temperatures
  below 10 K, which is consistent with weakly pinned domain walls. The dielectric
  loss does not show unusual behavior in the negative creep region of the temperature
  range, suggesting that the negative creep mechanism does not aect the behavior. In
  PZT, the hysteresis disappears below 30 K, as expected if its domain walls are pinned
  by grain boundaries. The implication for selecting the best material for positioning
  actuators that need large displacement involve d15. At cryogenic temperatures, one
  can use a LiNbO3 transducer/stack to achieve this. All three materials would be
  eective cryogenic ultrasonics sensors, but it would be challenging to use any of
  them as voltage sensors at frequencies below 1 kHz, since high input impedance
  would be needed. Given its nearly constant sensitivity for g15 and dielectric constant,
  LiNbO3 is probably the best sensor choice for precise measurements that cover a wide
  temperature range.

• Subjects / Keywords

  • LiNbO3
  • PMN-PT
  • PZT-5A
  • Cryogenic

• Graduation date

  Fall 2018

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3TM72H2P

• License

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