24 April 2012
BaSrTiO3/YIG microwave phase shifter with large two-degree-of-freedom tuning
Electron. Lett. -- 26 April 2012 -- Volume 48, Issue 9, p.508–509
C.Y. Zhu (1), H. Liu (1), V. Avrutin (1), C.Z. Lu (1), Ü. Özgür (1) and H. Morkoç (1)
(1) Virginia Commonwealth University, Department of Electrical and Computer Engineering, Richmond, USA
Ferroelectric material Ba0.5Sr0.5TiO3 has been grown on a polycrystalline ferrite yttrium iron garnet (YIG) substrate to achieve independent tuning of permittivity and permeability through the electric and magnetic field, respectively. A large dielectric constant and dielectric-constant tuning of the BST layer has been achieved with a simple deposition procedure by RF magnetron sputtering. Coplanar waveguides were fabricated on the bilayer structure to demonstrate the benefits of additional permeability tuning by external applied magnetic field: (i) to alleviate the impedance-mismatch caused by electric-field tuning of permittivity; (ii) to improve differential phase shift. A large differential phase shift of 77°/cm at 5 GHz for an applied electric field of 60 kV/cm has been achieved with the aid of the magnetic field.
Full text available on the IET Digital Library.
Browse or search all papers in the latest or past issues of Electronics Letters on the IET Digital Library.