How reliable are Hanle measurements in metals in a three-terminal geometry?

Oihana Txoperena, Marco Gobbi, Amilcar Bedoya-Pinto, Federico Golmar, Xiangnan Sun, Luis E. Hueso, and Fèlix Casanova

The authors show that Hanle measurements in three-terminal devices using aluminum and gold lead to Hanle- and inverted Hanle-like features which are not compatible with spin accumulation in these metals. The measured signals scale with the interface resistance of the tunnel barrier of the devices, suggesting that the origin of these anomalous signals arises from the tunnel barrier itself.

Appl. Phys. Lett. 102, 192406 (2013) | HTML | PDF

Magnetic imaging with a Zernike-type phase plate in a transmission electron microscope

Shawn Pollard, Marek Malac, Marco Beleggia, Masahiro Kawasaki, and Yimei Zhu

The authors demonstrate the use of a hole-free phase plate (HFPP) for magnetic imaging in transmission electron microscopy by mapping the domain structure in PrDyFeB samples. The HFPP, a Zernike-like imaging method, allows for detecting magnetic signals in-focus to correlate the sample crystal structure and defects with the local magnetization topography, and to evidence stray fields protruding from the sample.

Appl. Phys. Lett. 102, 192401 (2013) | HTML | PDF

Deterministic assembly of releasable single crystal silicon-metal oxide field-effect devices formed from bulk wafers

Tae-il Kim, Yei Hwan Jung, Hyun-Joong Chung, Ki Jun Yu, Numair Ahmed, Christopher J. Corcoran, Jae Suk Park, Sung Hun Jin, and John A. Rogers

Deterministic assembly of ultrathin metal oxide-semiconductor field-effect transistors released from the surfaces of bulk wafers with (111) orientation provides a route to high quality electronics on nearly any type of substrate. Device parameters and bias stability characteristics from transistors on sheets of plastic confirm the effectiveness of the approach and the critical roles of thermally grown layers of silicon dioxide for the gate dielectrics and passivation layers.

Appl. Phys. Lett. 102, 182104 (2013) | HTML | PDF

Strain-driven control of piezoelectricity in (Na,Bi)TiO₃-BaTiO₃ epitaxial thin films

Y. Tanaka, T. Harigai, H. Adachi, N. Sakamoto, N. Wakiya, H. Suzuki, and E. Fujii

Thermal strain effect on the piezoelectricity was investigated for (Na,Bi)TiO₃−BaTiO₃ (NBT−BT) thin films on various substrates with (100) and (110) orientations. The compressive-thermal strain caused an increase in the remnant polarization unaccompanied by a decrease in dielectric permittivity, which resulted in enhancement of the piezoelectric coefficient, e*₃₁.

Appl. Phys. Lett. 102, 192901 (2013) | HTML | PDF

Local-structure origins of the sustained Curie temperature in (Ba,Ca)TiO₃ ferroelectrics

Igor Levin, Victor Krayzman, and Joseph C. Woicik

While the lattice volume in the solid-solution Ba_1−xCaxTiO₃ decreases with increasing x, the Curie temperature remains unaffected, in contrast to Ba_1−xSrxTiO₃. We have determined the origin of this phenomenon by comparing the local structures in (Ba,Ca)TiO₃ and (Ba,Sr)TiO₃.

Appl. Phys. Lett. 102, 162906 (2013) | HTML | PDF