Please note, due to essential maintenance online transactions will not be possible between 02:30 and 04:00 BST, on Tuesday 17th September 2019 (22:30-00:00 EDT, 17 Sep, 2019). We apologise for any inconvenience.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Search for novel multi-functional materials, especially multiferroics, which are ferromagnetic above room temperature and at the same time exhibit a ferroelectric behavior much above room temperature, is an active topic of extensive studies today. Ability to address an entity with an external field, laser beam, and also electric potential is a welcome challenge to develop multifunctional devices enabled by nanoscience. While most of the studies to date have been on various forms of Bi- and Ba based Ferrites, rare earth chromites are a new class of materials which appear to show some promise. However in the powder and bulk form these materials are at best canted antiferromagnetics with the magnetic transition temperatures much below room temperature. In this presentation we show that thin films of YbCrO3 deposited by Pulsed Laser Deposition exhibit robust ferromagnetic properties above room temperature. It is indeed a welcome surprise and a challenge to understand the evolution of above room temperature ferromagnetism in such a thin film. The thin films are amorphous in contrast to the powder and bulk forms which are crystalline. The magnetic properties are those of a soft magnet with low coercivity. We present extensive investigations of the magnetic and ferroelectric properties, and spectroscopic studies using XAS techniques to understand the electronic states of the constituent atoms in this novel Chromite. While the amorphous films are ferromagnetic much above room temperature, we show that any observation of ferroelectric property in these films is an artifact of a leaky highly resistive material.
The low-cristobalite-type modification of Al0.5Ga0.5PO4 is prepared by annealing the amorphous precipitate of stoichiometric phosphate at 1300 °C. The phase purity of the sample is ascertained by powder X-ray diffraction. The crystal structure is refined by Rietveld refinements of the neutron and X-ray diffraction data of the polycrystalline powder. This compound crystallizes in an orthorhombic lattice with unit cell parameters, a=7.0295(8), b=7.0132(8), and c=6.9187(4) Å, V=341.08(6) Å3, Z=4 (Space group C 2221, No. 20). The crystal structure analysis reveals the random distribution of the Al3+ and Ga3+ having tetrahedral coordination with typical M–O (M=Al3+:Ga3+) bond lengths as 1.74 Å. Similarly, the P5+ have tetrahedral coordination with typical P–O bond lengths 1.52–1.54 Å. The Mo4 and PO4 tetraheda are linked by common corners forming a three-dimensional framework lattice. The details of the crystal structure are presented in this paper.
Email your librarian or administrator to recommend adding this to your organisation's collection.