Visible to Near-Infrared I/Q Modulators

The overall goal of this multi-phase SBIR program is to develop visible/near-IR (NIR) in phase /quadrature (IQ) modulators for operating in single side band suppressed carrier mode to allow for pure frequency shifting at wavelengths important for atomic and ionic systems. Wavelength shifting at visible and near IR wavelengths is currently primarily performed using acousto-optic modulators in free space setups. While effective, these AOMs are inherently lossy, require significant drive power, and are not easily integrated due to their free-space nature. In the telecom bands, a common approach to frequency shifting is to utilize I/Q modulators (also known as dual parallel Mach-Zehnder modulators) operating in single sideband suppressed carrier mode to generate a single sideband, tunable output with high extinction of parasitic tones. These modulators are generally fabricated in lithium niobate waveguides, which perform well at telecom wavelengths, but suffer from photorefractive effects at visible and near IR wavelengths. In this program, AdvR plans to utilize recently developed waveguides in MgO doped lithium niobate to allow for integrated functionality in a substrate resistant to photorefractive effects. This technology is expected to exceed Navy reach goals in a device-based configuration, leading to a high likelihood of commercial viability at the end of the Phase II program.