Project Details
Projekt
Nonlinear Optics with Whispering-Gallery-Mode Resonators made of Lithium Niobate Crystals
Applicant
Dr. Daniel Haertle
Subject Area
Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
Term
from 2004 to 2011
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5471245
Periodic poling of ferroelectric crystals like lithium niobate (LiNbO3) or lithium tantalate (LiTaO3) allows quasi phase matching for optical frequency conversion. By this means efficient optical parametric oscillation can be realized. However, so far most of such devices require external mirrors. Thus the devices become bulky and alignment is critical. Within the project we want to realize monolithic optical parametric oscillators (OPOs) based on periodically-poled LiNbO3 and LiTaO3 (PPLN and PPLT) that contain one or two photorefractive Bragg gratings ("distributed feedback laser", DFB laser, "distributed Bragg reflector laser", DBR laser). For this purpose we want to use LiNbO3 and LiTaO3 crystals that are doped with Mn as a photorefractive element that has low absorption in the visible but still shows strong photorefraction. Thermal fixing will be applied to make the gratings permanent. Furthermore, to avoid unwanted refractive-index and absorption changes ("optical damage") the Li content should be enhanced up to the maximum possible value by Li indiffusion ("vapor transport equilibration"). Realization of advanced monolithic DFB and DBR OPOs as well as improved understanding of photorefractive and ferroelectric properties of Li-enriched LiNbO3 and LiTaO3 are the goals of the project. The project is embedded into the research unit: Interaction with Project A2 allows to refine and to check the numerical simulations that will be performed by ourselves. Material knowledge gained and structures made in Project B1 can be of tremendous help. And Project B3 is very valuable for fabrication of the required domain structures as well as for characterization of the devices.
DFG Programme
Research Units
Participating Person
Professor Dr. Karsten Buse
