skip to main content


Title: Quasi-static optical parametric amplification

High-gain optical parametric amplification is an important nonlinear process used both as a source of coherent infrared light and as a source of nonclassical light. In this work, we experimentally demonstrate an approach to optical parametric amplification that enables extremely large parametric gains with low energy requirements. In conventional nonlinear media driven by femtosecond pulses, multiple dispersion orders limit the effective interaction length available for parametric amplification. Here, we use the dispersion engineering available in periodically poled thin-film lithium niobate nanowaveguides to eliminate several dispersion orders at once. The result is a quasi-static process; the large peak intensity associated with a short pump pulse can provide gain to signal photons without undergoing pulse distortion or temporal walk-off. We characterize the parametric gain available in these waveguides using optical parametric generation, where vacuum fluctuations are amplified to macroscopic intensities. In the unsaturated regime, we observe parametric gains as large as 71 dB (118 dB/cm) spanning 1700–2700 nm with pump energies of only 4 pJ. When driven with pulse energies><#comment/>10pJ, we observe saturated parametric gains as large as 88 dB (><#comment/>146dB/cm). The devices shown here achieve saturated optical parametric generation with orders of magnitude less pulse energy than previous techniques.

 
more » « less
Award ID(s):
1918549
PAR ID:
10369244
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optica
Volume:
9
Issue:
3
ISSN:
2334-2536
Format(s):
Medium: X Size: Article No. 273
Size(s):
Article No. 273
Sponsoring Org:
National Science Foundation
More Like this
  1. We experimentally demonstrate simultaneous turbulence mitigation and channel demultiplexing in a 200 Gbit/s orbital-angular-momentum (OAM) multiplexed link by adaptive wavefront shaping and diffusing (WSD) the light beams. Different realizations of two emulated turbulence strengths (the Fried parameterr0=0.4,1.0mm) are mitigated. The experimental results show the following. (1) Crosstalk between OAMl=+1andl=−<#comment/>1modes can be reduced by><#comment/>10.0and><#comment/>5.8dB, respectively, under the weaker turbulence (r0=1.0mm); crosstalk is further improved by><#comment/>17.7and><#comment/>19.4dB, respectively, under most realizations in the stronger turbulence (r0=0.4mm). (2) The optical signal-to-noise ratio penalties for the bit error rate performance are measured to be∼<#comment/>0.7and∼<#comment/>1.6dBunder weaker turbulence, while measured to be∼<#comment/>3.2and∼<#comment/>1.8dBunder stronger turbulence for OAMl=+1andl=−<#comment/>1mode, respectively.

     
    more » « less
  2. Thin-film lithium-niobate-on-insulator (LNOI) has emerged as a superior integrated-photonics platform for linear, nonlinear, and electro-optics. Here we combine quasi-phase-matching, dispersion engineering, and tight mode confinement to realize nonlinear parametric processes with both high efficiency and wide wavelength tunability. On a millimeter-long, Z-cut LNOI waveguide, we demonstrate efficient (1900±<#comment/>500%<#comment/>W−<#comment/>1cm−<#comment/>2) and highly tunable (−<#comment/>1.71nm/K) second-harmonic generation from 1530 to 1583 nm by type-0 quasi-phase-matching. Our technique is applicable to optical harmonic generation, quantum light sources, frequency conversion, and many other photonic information processes across visible to mid-IR spectral bands.

     
    more » « less
  3. Recently, our groups have introduced the notion of optical parametric amplification based on non-Hermitian phase matching wherein the incorporation of loss can lead to gain in this nonlinear optical process. Previous simulation results using second-order nonlinear optical coupled-mode theory have demonstrated the potential of this technique as an alternative to the stringent phase-matching condition, which is often difficult to achieve in semiconductor platforms. Here we fortify this notion for the case of third-order nonlinearity by considering parametric amplification in silicon nanowires and illustrate the feasibility of these devices by employing rigorous finite-difference time-domain analysis using realistic materials and geometric parameters. Particularly, we demonstrate that by systematic control of the optical loss of the idler in a four-wave mixing process, we can achieve efficient unidirectional energy conversion from the pump to the signal component even when the typical phase-matching condition is violated. Importantly, our simulations show that a signal gain of∼<#comment/>9dBfor a waveguide length of a few millimeters is possible over a large bandwidth of several hundreds of nanometers (∼<#comment/>600nm). This bandwidth is nearly 2 orders of magnitude larger than what can be achieved in the conventional silicon-photonics-based four-wave mixing process.

     
    more » « less
  4. The mid-IR spectroscopic properties ofEr3+doped low-phononCsCdCl3andCsPbCl3crystals grown by the Bridgman technique have been investigated. Using optical excitations at∼<#comment/>800nmand∼<#comment/>660nm, both crystals exhibited IR emissions at∼<#comment/>1.55,∼<#comment/>2.75,∼<#comment/>3.5, and∼<#comment/>4.5µ<#comment/>mat room temperature. The mid-IR emission at 4.5 µm, originating from the4I9/2→<#comment/>4I11/2transition, showed a long emission lifetime of∼<#comment/>11.6msforEr3+dopedCsCdCl3, whereasEr3+dopedCsPbCl3exhibited a shorter lifetime of∼<#comment/>1.8ms. The measured emission lifetimes of the4I9/2state were nearly independent of the temperature, indicating a negligibly small nonradiative decay rate through multiphonon relaxation, as predicted by the energy-gap law for low-maximum-phonon energy hosts. The room temperature stimulated emission cross sections for the4I9/2→<#comment/>4I11/2transition inEr3+dopedCsCdCl3andCsPbCl3were determined to be∼<#comment/>0.14×<#comment/>10−<#comment/>20cm2and∼<#comment/>0.41×<#comment/>10−<#comment/>20cm2, respectively. The results of Judd–Ofelt analysis are presented and discussed.

     
    more » « less
  5. A novel optical frequency division technique, called regenerative harmonic injection locking, is used to transfer the timing stability of an optical frequency comb with a repetition rate in the millimeter wave range (∼<#comment/>300GHz) to a chip-scale mode-locked laser with a∼<#comment/>10GHzrepetition rate. By doing so, the 300 GHz optical frequency comb is optically divided by a factor of30×<#comment/>to 10 GHz. The stability of the mode-locked laser after regenerative harmonic injection locking is∼<#comment/>10−<#comment/>12at 1 s with a1/τ<#comment/>trend. To facilitate optical frequency division, a coupled opto-electronic oscillator is implemented to assist the injection locking process. This technique is exceptionally power efficient, as it uses less than100µ<#comment/>Wof optical power to achieve stable locking.

     
    more » « less