Multi-wavelength Sources based on Parametric Amplification
US20260188964A1
Abstract
An apparatus includes a single photonic crystal fiber including a first end, a propagation length, and a second end. The single photonic crystal fiber includes a varying dispersion that varies along the propagation length. The single photonic crystal fiber includes a varying mode field diameter that varies along the propagation length. The first end includes a first dispersion at a pump wavelength, the first dispersion being normal. The second end includes a second dispersion at the pump wavelength, the second dispersion being anomalous. The first end includes a first mode field diameter at the pump wavelength. The second end includes a second mode field diameter at the pump wavelength, the second mode field diameter being smaller than the first mode field diameter.
Description (excerpt)
CROSS REFERENCE TO RELATED APPLICATION This divisional patent application claims benefit from U.S. patent application Ser. No. 18/080,063 filed on Dec. 13, 2022, which was a continuation-in-part patent application that claimed benefit from U.S. patent application Ser. No. 16/545,799 filed on Aug. 19, 2019, which is herein incorporated by reference and which in turn claims the benefit of U.S. Provisional Patent Application No. 62/765,283 filed on Aug. 20, 2018, which is herein incorporated by reference. FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT The United States Government has ownership rights in this invention. Licensing inquiries may be directed to Office of Technology Transfer, US Naval Research Laboratory, Code 1004, Washington, DC 20375, USA; +1.202.767.7230; techtran@nrl.navy.mil, referencing NC 109,181-US4. BACKGROUND Technical Field The embodiments herein generally relate to optical communication systems, and more particularly to optical amplification systems for achieving high brightness visible to SWIR sources. DESCRIPTION OF THE RELATED ART Parametric amplification in a glass optical fiber is a third order nonlinear process dependent upon χ (3) of the glass. Parametric amplification operates by the process of four-wave mixing, involving the interaction of four optical waves. In parametric amplification, one or two pump waves at frequency ω 1 and ω 2 amplifies a signal wave at frequency ω 3 and generates an idler wave at frequency ω 4 . In the one pump, or degenerate, parametric processes, ω 1 =ω 2 . The frequencies of the signal and idler waves are related to the frequencies of the pump waves by the relation ω 1 +ω 2 =ω 3 +ω 4 . To achieve parametric amplification, phase matching between the pump, signal, and idler waves is required. The signal wave and/or idler wave to be amplified may be coupled into the fiber or parametrically generated spontaneously in the fiber through four-wave mixing. Phase matching can be achieved by careful control of the dispersion of the fiber. For industry, materials processing, biological sensing, and laser display technology for next generation projection theater also require laser sources at wavelengths not available in current laser sources. Of particular interest for industry is generation of sources in the UV and blue which is of interest in materials processing of copper and gold and blue lasers for display technology. Similarly, available laser sources do not always access the wavelength and wavebands of interest and needed for some commercial or public-sector applications. Some previous solutions for achieving high brightness infrared fiber parametric amplifiers and light sources are described in U.S. Pat. Nos. 9,570,873 and 9,577,401, the complete disclosures of which, in their entireties, are herein incorporated by reference. While the techniques described by these patents and others were sufficient for the purposes for which they were designed, there remains a need for a new technique to achieve high brightness, multi-wavelength sources over a broad wavelength region, particularly from the UV to SWIR wavelength regions. SUMMARY OF THE INVENTION An embodiment of the invention includes an apparatus. The apparatus includes a first photonic crystal fiber. The first photonic crystal fiber includes a first dispersion at a pump wavelength. The first dispersion is normal. The first photonic crystal fiber includes a first mode field diameter at the pump wavelength. The apparatus also includes a second photonic crystal fiber coupled to the first photonic crystal fiber and outputs a broadband spectrum. The second photonic crystal fiber includes a second dispersion at the pump wavelength. The second dispersion is anomalous. The second dispersion is smaller than the first dispersion. The second photonic crystal fiber includes a second mode field diameter at the pump wavelength. The second mode field diameter is smaller than the first mode field diameter. Optionally, the apparatus further includes a pump laser, in operation, emitting an electromagnetic radiation wave comprising the pump wavelength. The apparatus further includes a coupler coupled to the pump laser and to the first photonic crystal fiber. Optionally, the pump laser comprises a Ytterbium (Yb) doped fiber laser with a linewidth <1 nm. Optionally, the first photonic crystal fiber and/or the second photonic crystal fiber includes a silica, solid core photonic crystal fiber. The silica, solid core photonic crystal fiber includes a core diameter between 2 μm and 25 μm. Optionally, a signal laser is coupled to the first photonic crystal fiber. The signal laser, in operation, emits a signal wavel
Filing details
- Inventors
- Rafael R. Gattass
- Assignee
- The Government Of The United States Of America, As Represented By The Secretary …
- Filed
- Feb 27, 2026
- Granted
- Application pending
Bibliographic data and excerpted text sourced from Google Patents (public record) as part of IP TechMatch's current-filings monitor. This filing is not part of the 2019 historical archive. For the authoritative full text, drawings, and legal status, see the source links above or consult USPTO records directly.