The influence of a combined doping with Zn and In on the optical properties of lithium niobate is studied. While each of these dopants is known to improve the material’s nonlinear optical properties, it is an open question whether further improvements, especially of the nonlinear optical features, can be achieved by a suitable combination of dopants. Our measurements show that lithium niobate imposes certain limits which cannot be overcome. This can be described by a simple model which is based on the defect structure of lithium niobate.

No abstract

No abstract

No abstract

The low-level rf control system currently commissioned throughout the Spallation Neutron Source (SNS) LINAC evolved from three design iterations over 1 yr intensive research and development. Its digital hardware implementation is efficient, and has succeeded in achieving a minimum latency of less than 150 ns which is the key for accomplishing an all-digital feedback control for the full bandwidth. The control bandwidth is analyzed in frequency domain and characterized by testing its transient response. The hardware implementation also includes the provision of a time-shared input channel for a superior phase differential measurement between the cavity field and the reference. A companion cosimulation system for the digital hardware was developed to ensure a reliable long-term supportability. A large effort has also been made in the operation software development for the practical issues such as the process automations, cavity filling, beam loading compensation, and the cavity mechanical resonance suppression.