Gisele L Maxwell

US Patent:

20110067626, Mar 24, 2011

Filed:

Sep 22, 2009

Appl. No.:

12/586439

Inventors:

Gisele Maxwell - Cottonwood CA, US

International Classification:

C30B 13/00

US Classification:

117204

Abstract:

A laser heated pedestal growth system for growing a periodically poled, single crystal rod having domain interfaces substantially parallel to the rod's long axis. Suitable crystalline ferroelectric feed materials have a Curie temperature no greater than 200 C. below its melting point and include Lithium Niobate and MgO doped Lithium Niobate. The system comprises:i) a laser that generates first and second laser beams;ii) the first laser beam being a molten zone beam for melting the feed material and the second being an afterheater beam;iii) two spaced apart wire electrodes situated on either side of the crystal rod parallel to the growth direction of the crystal rod, and connected to an alternating electrical current source which creates an electric field between the electrodes which is parallel then anti-parallel to the crystal rod growth axis;iv) an Infra-Red scanner and computer controlled feedback system for controlling the axial and radial temperature gradients in the crystal rod in the region between the electrodes.

US Patent:

20090020069, Jan 22, 2009

Filed:

Jan 25, 2008

Appl. No.:

12/020382

Inventors:

Eugene Standifer - Menlo Park CA, US
Gisele Maxwell - Palo Alto CA, US

International Classification:

C30B 13/24

US Classification:

117204

Abstract:

A post-growth optical afterheater system includes an appropriate choice of optical heat source for the single crystal material to be heated, a power adjustment module for controlling the optical power heating the crystal, and suitable focusing optics to focus the heating beam onto the crystal. The heat source may be a laser of appropriate wavelength or an incoherent source of sufficient power. In one embodiment, the power adjustment module is an optical attenuator, either of crossed-polarizer design or of intersecting wire grids. The focusing optics may be refractive, reflective, or catadioptric, depending on factors such as diameter, cost target, and space available in the crystal growth apparatus.