title: Pressure-induced reversal between thermal contraction and expansion in ferroelectric PbTiO3.
abstract: Materials with zero/near zero thermal expansion coefficients are technologically important for applications in thermal management and engineering. To date, this class of materials can only be produced by chemical routes, either by changing chemical compositions or by composting materials with positive and negative thermal expansion. Here, we report for the first time a physical route to achieve near zero thermal expansion through application of pressure. In the stability field of tetragonal PbTiO3 we observed pressure-induced reversals between thermal contraction and expansion between ambient pressure and 0.9 GPa. This hybrid behavior leads to a mathematically infinite number of crossover points in the pressure-volume-temperature space and near-zero thermal expansion coefficients comparable to or even smaller than those attained by chemical routes. The observed pressures for this unusual phenomenon are within a small range of 0.1-0.9 GPa, potentially feasible for designing stress-engineered materials, such as thin films and nano-crystals, for thermal management applications.
authors.affiliation: 1] LANSCE, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA [2] National Lab for Condensed Matter Physics, Institute of Physics, CAS, Beijing, 100190, China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Zhu
authors.affiliation: LANSCE, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: EES Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: Hongwu
authors.initials: H
authors.lastname: Xu
authors.affiliation: LANSCE, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: Sven C
authors.initials: SC
authors.lastname: Vogel
authors.affiliation: National Lab for Condensed Matter Physics, Institute of Physics, CAS, Beijing, 100190, China.
authors.forename: Changqing
authors.initials: C
authors.lastname: Jin
authors.affiliation: Aalto University, School of Science, Department of Applied Physics, FI-00076 Aalto, Finland.
authors.forename: Johannes
authors.initials: J
authors.lastname: Frantti
authors.affiliation: 1] National Lab for Condensed Matter Physics, Institute of Physics, CAS, Beijing, 100190, China [2] HiPSEC, Department of Physics and Astronomy, University of Nevada, Las Vegas, Nevada 89154, USA.
authors.forename: Yusheng
authors.initials: Y
authors.lastname: Zhao